Oka jimas Folia Anat. Jpn., 57(1) : 55-78, May 1980

The Facial Artery of the Dog

By

MOTOTSUNA IRIFUNE

Department of Anatomy, Osaka Dental University, Osaka (Director: Prof. Y. Ohta) (with one textfigure and thirty-one figures in five plates)

-Received for Publication, November 10, 1979-

Key words: Facial artery, Dog, Plastic injection, Floor of the mouth. Summary. The course, branching and distribution territories of the facial artery of the dog were studied by the acryl plastic injection method. In general, the facial artery was found to arise from the external carotid between the points of origin of the lingual and posterior auricular arteries. It ran anteriorly above the digastric muscle and gave rise to the styloglossal, the submandibular glandular and the ptery- goid branches. The artery continued anterolaterally giving off the digastric, the inferior masseteric and the cutaneous branches. It came to the face after sending off the submental artery, which passed anteromedially, giving off the digastric and mylohyoid branches, on the medial surface of the mandible, and gave rise to the sublingual artery. The gingival, the genioglossal and sublingual plical branches arose from the vessel, while the submental artery gave off the geniohyoid branches. Posterior to the mandibular symphysis, various communications termed the sublingual arterial loop, were formed between the submental and the sublingual of both sides. They could be grouped into ten types. In the face, the facial artery gave rise to the mandibular marginal, the anterior masseteric, the inferior labial and the buccal branches, as well as the branch to the superior, and turned to the superior labial artery. As variations, the submental artery arose directly from the external carotid, and an accessory inferior alveolar artery arose from the facial in a few cases.

Introduction cated course and considerable ramifica- tions exist before and after it passes General descriptions of the facial artery across the mandibular basis to the face. of the dog were given by Ellenberger The present paper gives precise and de- and Baum (1891) and Miller et al. (1964) tailed descriptions on the course, branch- in their textbooks on the anatomy of the ing and distribution territories of the dog. Detailed observations have not yet facial artery of the dog, briefly discussing been performed for the whole ramifica- comparative features of the vessel in tions of the artery, although the angular other mammalian species, especially the branch of the mouth and the superior relationships between the branching of labial artery were extensively investigated the artery and that of other vessels in by Hanai (1964). the floor of the mouth. The artery takes a somewhat compli-

55 56 M. Irifume

Materials and Methods of the lingual and the facial. In the other four cases, the facial artery in all its Acryl plastic injection (Taniguchi et al. course displayed features like the sub- 1952, 1955) was performed in 45 adult mental artery, which is a branch of the dogs through the common caroted arteries. facial, but an artery which showed fea- Forty of the injected heads were treated tures like the usual facial artery arose with sodium hydroxide solution to prepare from the lateral wall of the external corrosion specimens of the carotid system. carotid right proximal to the division be- These were used for statistical assess- tween the superficial temporal and maxil- ment of variations in the facial artery lary arteries (Fig. 3), and the transverse and its ramifications, and also for meas- facial arose from the superficial temporal urement of the vessels. The other five near its origin (Fig. 3). injected heads were preserved in 10% The facial artery ran anteriorly between formalin solution for dissection, and one the styloglossal and medial pterygoid was used to make histological slides by muscles, superomedial to the digastric. decalcification, embedding in celloidin, It gave off the styloglossal branch and serial sectioning at a thickness of 200 pm the submandibular glandular branch, then (50 pm in every tenth section) in the the submental artery (the sublingual ar- frontal plane, and staining with hema- tery of Ellenberger and Baum 1891 and toxylin-eosin. The corrosion casts of the Miller et al. 1964) anteriorly and slightly carotid system, formalin-preserved ma- medially, and continued anterolaterally terials and serial slides were used to de- between the insertion of the digastric and termine the detailed anatomy of the the medial pterygoid, giving off the di- facial artery, its ramifications and rela- gastric, the inferior masseteric and the tionships with surrounding structures. cutaneous branches en route. The artery then came to the face via the facial vas- Results cular notch and passed superoanteriorly between the mimic muscles, where the In most cases, the facial artery arose mandibular marginal branch, the anterior from the external carotid artery between masseteric branch, the interior labial ar- the points of origin of the lingual and tery and the buccal branch originated. posterior auricular arteries. The parent The facial artery finally turned to the artery (2.5-3.5, M. 3.0 mm in diameter) in superior labial artery after curving an- this region arched superolaterally along teriorly along the superior margin of the the superior margin of the digastric buccinator muscle and giving off the an- muscle after giving off the lingual artery gular branch of the mouth and the branch anteroinferiorly in the medial side of the to the superior behind the oral angle. muscle about 10 mm distal to the origin. The facial arteries bilaterally in one In 76 of the 80 examples observed, the head gave off anteriorly the accessory in- facial artery (2.2-3.2, M. 2.9 mm) derived ferior alveolar artery from the superior inferolaterally from the anteroinferior wall when the facial crossed above the wall of the arching between the stylog- submandibular duct anterolaterally (Fig. lossal and digastric muscles in front of 4). This vessel passed anteriorly together the tympanic bulla (Figs. 1, 2). In one of with the parent artery, medial to the the 76 cases, the posterior auricular artery medial pterygoid muscle up to its anterior arose proximal to the origin of the lingual, margin, where it bent superiorly between but no variations were seen in the origins the posterior margin of the mylohyoid The Facial Artery of the Dog 57 and medial pterygoid. It finally entered the styloglossal anterolaterally. In nine the mandibular foramen along and inferior of the 60 cases, the styloglossal arose in to the satellite nerve and displayed the common with the submandibular glandu- usual distribution features such as the lar branch (Fig. 5), and in eight other inferior alveolar artery within the man- cases directly from the external carotid dible. The inferior alveolar artery as near the origin of the facial (Fig. 6). The original vessel, however fine, arose from branch immediately supplied the stylog- the maxillary artery in common with the lossal muscle from its ventral side. In posterior deep temporal and supplied only three of the above 43 cases, a small twig the first and second molar teeth (Fig. 4). of the branch ran ventrally to supply the The facial artery observed in the four digastric (Fig. 7). above-mentioned cases, which arose right 2. Submandibular glandular branch proximal to the termination of the ex This branch (0.41-1.30, M. 0.74 mm) in ternal carotid, passed inferiorly and slight- all 80 examples arose from the infero-

- ly laterally between the posterior margin medial wall of the facial (Figs. 1, 2, 6, 7) of the mandibular ramus and the parotid or the submental arising directly from gland. From its anterior wall anteriorly, the external carotid in 75 cases (Fig. 3), it gave off the masseteric branch which in common with the styloglossal branch supplied the posterior region of the inser- (Fig. 5) in nine cases, or in common with tion of the superficial layer of the mas- the pterygoid branch in five cases (Fig. 8). seter. When the artery bent supero- It also arose in common with the digastric anteriorly along the inferior margin of branch of the submental with usual fea- the masseter, two or three medial ptery- tures in five cases (Fig. 9). The glandular goid branches from its superomedial wall branch crossed the submandibular duct and two to four masseteric branches from above the digastric and immediately made the superolateral wall, were derived. The a U-curve posterolaterally up to the glan- former supplied the superficial region of dular hilus along the upper margin of the the insertion of the medial pterygoid. digastric (Fig. 2). The styloglossal or The latter supplied the insertion of the the medial pterygoid branch separated superficial layer of the masseter, of which from the glandular branch at the U-curve a thicker branch may have been the in- (Fig. 8). The submandibular branch sent ferior masseteric branch, which in the twigs to the submandibular duct and the usual case arises from the facial distal to sublingual gland (Figs. 2, 5, 7, 9). the submental artery (Fig. 3). The facial 3. Pterygoid branch artery in these four cases did not reveal This branch (0.31-0.55, M. 0.43 mm) in any unusual features in the face. all 80 examples arose from the supero- medial wall when the facial or the sub- Branches : mental arising directly from the external 1. Styloglossal branch carotid crossed anterolaterally above the This branch (0.31-0.50, M. 0.41 mm), one submandibular duct and medial to the in- in number, was seen in 60 of the 80 ex- sertion of the medial pterygoid muscle amples observed. In 43 cases, it arose (Fig. 2). The branch in 47 cases, after from the superior wall of the facial or giving off twigs to the sublingual gland, the submental right distal to their points the oral mucosa or the styloglossal, but of origin (Figs. 2, 4). In this region, the no twigs in 28 cases (Figs. 11, 12), sup- facial or the submental artery ran obli- plied the insertion of the muscle, ramify- quely across ventral to the long head of ing arborescently on its medial side (Fig. 58 M. Irifume

8). The branch arose in common with the facial vascular notch after passing the submandibular branch in five cases between the inferoanterior edge of the (Fig. 8). masseter and the posterior edge of the The twigs to the sublingual, the oral insertion of the digastric (Figs. 1, 2, 14). mucosa and the styloglossal displayed In the other four cases, the submental various features in their origins as fol- arose directly anteriorly from the external lows. The twig to the sublingual gland, carotid like the facial artery (Fig. 3), and seen in 37 of the 80 examples, arose from at the point where the submental in the the pterygoid branch in 22 cases (Fig. 10) usual case leaves the facial, it gave off a and from the facial in 15 cases (in com- twig which extended to the anterior end mon with the branch to the oral mucosa of the insertion of the masseter and in 7 of these cases) (Fig. 11). It supplied turned to the digastric branch, not be- the sublingual gland and the submandi- yond the notch (Fig. 3). bular duct. The twig to the oral mucosa, The submental passed anteriorly and seen in 33 cases, arose from the pterygoid slightly medially between the insertions branch in 17 cases, from the facial in 16 of the mylohyoid and the digastric on the cases (Fig. 12) and in common with the medial surface of the mandible together twig to the sublingual gland in 7 of these with the mylohyoid nerve (Fig. 14). In cases (Fig. 11). It ran anteriorly medial this course, two to six (four on average) to the medial pterygoid muscle, anasto- digastric branches (0.25-0.62, M. 0.42 mm) mosing with the lingual branch (Suwa et were derived from the inferomedial wall al. 1978) of the posterior deep temporal of the artery and three to ten (six on at the anterior margin of the muscle, average) mylohyoid branches (0.31-0.56, M. and was distributed to the mucous plica 0.46 mm) from the superomedial wall behind the upper and lower last molar (Figs. 15, 16). The artery then continued teeth, the lingual gingivae of the molars, to pass beneath the mylohyoid, and two and sometimes the mucosa inferoposterior to twelve (seven on average) mylohyoid to the palatine tonsil. This branch was branches arose from its superior and not obvious when the lingual branch was medial walls (Figs. 15, 16). well developed. The twig to the stylog- The artery finally reached the antero- lossal, seen in 9 cases, arose from the lateral end of the mylohyoid, where the pterygoid branch and ran superomedially sublingual artery (1.2-2.1, M. 1.6 mm) was to supply the venter of the medial ptery- derived superoanteromedially (Figs. 15, 16. goid from its lateral side (Fig. 13). 17), and ran anteromedially just inferior 4. Submental artery (the sublingual to the origins of the genioglossal and artery of Ellenberger and Baum 1891 geniohyoid muscles on the mandible up and Miller et al. 1964) to the inferoposterior end of the mandi- This artery (1.7-2.6, M. 2.10 mm) in 76 bular symphysis, where the sublingual of the 80 examples observed, arose an- arterial loop was formed (Figs. 17, 18). teriorly from the facial artery when it En route, the artery sent off superiorly followed a course between the medial four to seven (five on average) genio- pterygoid and styloglossal muscles to the hyoid branches (0.12-0.50, M. 0.22 mm) posterolateral end of the mylohyoid muscle (Fig. 17). after running anterolaterally across the a) Digastric branch : submandibular duct above the digastric This branch descended to the upper muscle (Figs. 1, 2, 9, 14). The facial bent margin of the digastric and supplied its anterolaterally and came to the face via insertion (Figs. 15, 16), while it gave off The Facial Artery of the Dog 59 twigs to the venter of the mylohyoid of the genioglossal and the anterior mar- near its posterior margin (Fig. 16) and gin of the mylohyoid, then anteromedially part of the platysma, and sometimes in along the upper margin of the origin of 16 cases to the anterior margin of the the genioglossal and beyond the genio- insertion of the medial pterygoid muscle hyoid up to the posterior end of the (Fig. 19). mandibular symphysis, to participate in b) Mylohyoid branches : the formation of the sublingual arterial Those branches which arose from the loop (Figs. 17, 18, 23). superior or superolateral wall of the ar- When the sublingual ran along the tery supplied the origin of the mylohyoid genioglossal muscle, it sent off four to (Figs. 15, 16, 17). One or two of them seven (five on average) gingival branches supplied the sublingual gland and sub- (0.14-0.48, M. 0.24 mm) superoanteriorly mandibular duct after penetrating its from its superior wall and seven to thir- venter. Those supplying the duct ran teen (nine on average) genioglossal posteriorly along its upper or lower side branches (0.68-0.72, M. 0.5G mm) medially and anastomosed with the same named (Fig. 23). branches of the facial, the pterygoid Gingival branches ran anterolaterally branch (Fig. 20) or the lingual branch on the medial surface of the mandible to (Fig. 16). The digastric branches arising supply the lingual gingivae of all teeth on the distal side were distributed to the anterior to the first lower molar, and gingivae of the lower molars and the sub- twigs from them anastomosed with the lingual plica after penetrating the mylo- same named branches of the mental hyoid muscle, while small twigs from arteries (Fig. 23). The anteriormost one them anastomosed with the inferior labial among them, which was the thickest and gingival branches of the mental (0.29-0.46, M. 0.36 mm), supplied the lin- arteries through the interdental papillae, gual gingivae of all teeth anterior to the but did not supply the inferior surface of first lower premolar (Fig. 23), but in ele- the tongue. ven cases arose directly from the sub- Those branches which arose from the mental and ran anterosuperiorly on the inferior or inferomedial wall of the artery mandible (Fig. 24). ran medially and supplied the venter of The genioglossal branch passed medially the mylohyoid, anastomosing with the between the submandibular duct and the peripheries of the branch to the inferior sublingual artery, and after sending off (Okano 1960) of the hyoid branch of the superiorly three or four sublingual plical lingual artery (Fig. 21). Some of them branches (0.10-0.24, M. 0.17 mm), supplied supplied the geniohyoid muscle after pene- the origins of the genioglossal and the trating the mylohyoid superiorly, and geniohyoid from their upper surfaces others supplied the geniohyoid muscle (Figs. 24, 25). As mentioned above, the after penetrating the mylohyoid superior-. plical branches arose from the genioglossal ly, or the subcutaneous tissue of the sub- branch in 60 cases, but directly from the mandibular region after penetrating the sublingual in the other cases (Fig. 24). platysma inferiorly, anastomosing with They gave off twigs to the sublingual the opposite fellows and the cutaneous gland, the submandibular duct and finally branch of the submental (Fig. 22). the sublingual plica running supero- c) Sublingual artery : anteriorly medial to the duct, but did not This vessel ran superoanteromedially extend down to the sublingual mucosa between the posterior end of the origin (Fig. 25). The proximal most genioglos- 60 M. Irifume sal branch passed posteriorly above the ing the four arteries but not between the mylohyoid along the submandibular duct bilateral sublingual arteries (one case). to supply these structures, anastomosing Type IV. Anastomoses between the with the peripheries of the mylohyoid sublingual and the submental on each branch of the submental (Fig. 20) after side, but no bilateral communications (five giving off twigs to the geniohyoid and cases). the genioglossal. In some cases, the Type V. Anastomoses between the branch arose directly from the submental bilateral sublingual arteries and between proximal to the origin of the sublingual the bilateral submental arteries, but no (Fig. 17). communications on the respective sides d) Geniohyoid branch : (two cases). This consisted of medial and superior Type VI. Anastomoses between the branches (Figs. 17, 21). The former pas- bilateral sublingual arteries and to the sed medially inferior to the geniohyoid right or left submental (four cases). muscle and supplied it and the genioglos- Type VII. Anastomoses between the sal muscle (Figs. 17, 21), after giving off bilateral submental arteries and to the cutaneous branches inferiorly, which sup- right or left sublingual (four cases). plied the skin of the mental area, anas- Type VIII. Unilateral anastomosis be- tomosing with those of the anterior and tween the submental and sublingual ar- middle mental arteries and the mylohyoid teries only (six cases). branch (Fig. 22). The latter ran superiorly Type IX. Anastomosis between the between the genioglossal and the mandi- bilateral sublingual arteries only (one ble, and supplied mainly the origin of the case). genioglossal and partly the geniohyoid Type X. No anastomosis between any (Fig. 17). of the four arteries (four cases). e) Sublingual arterial loop: From the loop, one to three branches The anastomosis between the bilateral were derived for supplying the mandibular submental arteries was located on the symphysis mainly (Figs. 18, 23), as well inferior side of the origin of the genio- as part of the median area of the posterior hyoid. The anastomosis between the surface of the mandible, but did not com- bilateral sublingual arteries was on its municate with the inferior incisive branch superior side (Fig. 23), and the anastomosis (Mizutani 1977) of the inferior alveolar between the unilateral submental and the artery (Fig. 26). One of them perforated unilateral sublingual was on its lateral the symphysis and communicated with side (Figs. 17, 18). Accordingly, an ar- the periosteal branch (Mizutani) of terial loop was formed by these four the anterior mental artery and the cut- arteries, termed the sublingual arterial aneous branch of the geniohyoid branch loop, which could be grouped into the fol- of the submental at the median area of lowing ten types according to the features the anterior surface of the mandible (Fig. of the anastomoses as shown in the text- 26). In cases of type X, twigs of the figure. submental and sublingual arteries came Type I. Obvious anastomoses between to the symphysis, and a twig which per all four arteries (11 cases). forated it was derived from the left sub-

- Type II. Obvious anastomoses involv- mental in three of the four cases and ing the four arteries but not between the from the right submental in the remain- bilateral submental arteries (two cases). ing case. Type III. Obvious anastomoses involv- The Facial Artery' of the Dog

AE IX X Textfigure. Ten types of sublingual arterial loop based on communications between the sublingual (o) and submental (i) arteries of both sides.

5. Digastric branch and inferior the 80 examples observed, the digastric masseteric branch branch gave rise to the submandibular When the facial ran anterolaterally at lymphnodular branch (Miyata 1966) (Fig. the superolateral end of the insertion of 27). the digastric after giving off the sub- 6. Cutaneous branch mental artery, one or two digastric This branch, seen in 38 of the 80 ex- branches (one. in 38 cases and two in amples observed, arose from the inferior eight cases) were derived posteriorly from wall of the facial before this artery pas- the posterior or posterosuperior wall of sed through the facial vascular notch the facial, and one to three inferior mas- (Fig. 27). It supplied the platysma mainly seteric branches (one in 37 cases, two in and the skin of the submandibular region 36 cases and three in seven cases) infero- after perforating the muscle (Fig. 28). In laterally from the lateral wall (Fig. 27). 18 of the 38 cases, it gave rise to the The digastric branch passed posteriorly submandibular lymphnodular branch (Mi- along the upper margin of the muscle yata 1966). and supplied its insertion, and also the 7. Mandibular marginal branch and anterior part of the insertion of the anterior masseteric branch medial pterygoid in twenty cases, in These branches were the first rami- which the digastric branch of the sub- fication when the facial came to the face. mental did not supply it. The mandibular marginal branch arose The inferior masseteric branch ran in- anteriorly from the anterior wall of the ferolaterally to the inferior end of the facial in 60 of the 80 examples observed, insertion of the masseter, where it bent and the anterior masseteric superopos- superiorly to supply the insertion of the teriorly from the superior wall in all the first layer of its superficial layer (Yoshi- examples (Fig. 29). However, the origin kawa et al. 1961) (Figs. 2, 27). In 14 of of the former changed places with that 62 M. Irifume

of the latter in sixteen cases, so the an- 9. Inferior labial artery terior masseteric followed a course up to This artery (one in 74 cases and two in the anterior margin of the masseter. six cases) was found in 68 cases to arise The mandibular marginal branch ex- anteriorly from the anterior wall of the tended anteriorly onto the lateral margin facial when it ran anterosuperiorly be- of the mandibular basis up to about 20 mm tween the posteroinferior end of the inferior to the oral angle (Fig. 29). In mandibular ramus and the anterior mar- eleven cases, it sent off the submandi- gin of the masseter on the lateral surface bular lymphnodular branches (Miyata) of the mandible (Figs. 29, 31). In the (Fig. 29). other twelve cases, it arose through a The anterior masseteric (one in 48 cases, common trunk (3-9 mm in length) with two in 29 cases and three in three cases) the angular branch of the mouth (Fig. passed superiorly and slightly posteriorly 30). The artery passed anteriorly on the on the mandibular ramus, and supplied lateral surface of the buccinator muscle the insertion of the intermedius of the and divided into the superficial and deep masseter (Yoshikawa et al. 1961) and the an- branches just behind the oral orbicular terior region of the deep layer. At the muscle (Figs. 29, 30, 31). It gave rise to upper margin of the insertion of the in- two to four twigs which supplied the termedius, it anastomosed with the branch buccinator and the buccal gland, and one to the inferior (Fujiwara 1970) of the or two cutaneous twigs which supplied masseteric artery and at its inferior mar- the skin ranging from the inferoanterior gin with the masseteric branch (Fujiwa- region of the masseter to the inferopos- ra) of the transverse facial (Fig. 30). terior region of the lower lip, anastomos- Finally, the branch gave off the buccal ing with the peripheries of the branch to branch from its superior wall in 16 of the superior, of the mylohyoid branch of the 80 examples observed (Fig. 29). the submental artery and of the superior 8. Buccal branch thyroid artery (Fig. 28). Twigs, some- This branch arose from the facial pro- times arising from the superficial branch ximal to the origin of the inferior labial of the cutaneous branch, passed anteriorly (Fig. 31) in 51 of the 80 examples observed, along the inferior labial vein in the lateral from the anterior masseteric in 16 cases side of the mandible, and anastomosed (Fig. 29), from the facial distal to the with the inferior labial (Mizutani 1977) origin of the inferior labial in five cases, and the muscular branches (Mizutani) from the inferior labial in four cases, of the posterior and middle mental arteries from the superior labial in three cases (Fig. 30). (Fig. 30), and from the angular branch of The superficial branch ran anteriorly the mouth in one case. The branch gave between the mimic muscles and supplied off twigs to the buccinator muscle and them in the lower lip located between divided into the branch to the supero- the oral angle and the fourth premolar posterior and the branch to the superior tooth, anastomosing with the superficial along the anterior margin of the mandi- branch (Hanai 1964) of the angular branch bular ramus on its lateral surface. The and the inferior labial branch (Mizutani) former supplied the intermediate and deep of the middle and posterior mental layers of the masseter from its anterior arteries (Fig. 31). The deep branch pene- margin, and the latter supplied the buc- trated the mimic muscles and supplied cinator, anastomosing with the peripheries the buccal and the inferior labial glands of the buccal artery (Figs. 29, 30). and the oral mucosa between the oral The Facial Artery of the Dog 63 angle and fourth premolar, anastomosing Discussion with the deep branch of the angular branch of the mouth (Hanai 1964) (Fig. 31). In general, the origin of the facial ar- 10. Branch to the superior tery lies distal to the origin of the lingual This branch, one or two in number on the external carotid. However, in four (Figs. 28, 29), arose from the superior cases the facial arose from the external wall of the following vessels : from the carotid right proximal to its terminal facial when it ran superoanteriorly in the division and was distributed only to the medial side of the buccinator muscle in face, not to the submandibular region, 59 of the 80 examples observed (Fig. 30), and the transverse facial arose near the from the superior labial artery when it origin of the superficial temporal with ran along the superior margin of the the usual branching features. Although muscle in 17 cases (Fig. 29), and from the facial artery in these cases was simi- the angular branch running anteriorly in lar to the transverse facial of the goat the lateral side of the muscle in the other in its distribution territory, the transverse four cases (Fig. 30). facial also appears as a usual feature of The branch ran superiorly across, la- the dog, and the submental arose directly teral to the facial vein, and gave off from the external carotid distal to the twigs to the buccinator muscle and the origin of the lingual. Facial and sub- parotid duct. It finally supplied the skin mental arteries as seen in these four cases of the anterior surface (posterior to the in the dog have been reported in man by infraorbital foramen) of the maxilla Adachi (1928). through the lateral surface of the zygo- The submandibular glandular branches matic bone. The peripheries of the of the dog have been described by Ellen- branch anastomosed with the inferior or- berger and Baum (1891, 1943), Nickel et bital marginal branch (Arai 1978) of the al. (1976), Miller et al. (1964) and Taka- malar artery, the inferior palpebral branch shima (1967). The facial artery of the of th6 lacrimal artery, the cutaneous dog was separated by the digastric muscle branches of the infraorbital and the trans- from the submandibular gland, differing verse facial arteries. Proximal twigs of from the situation in man, in which the the branch supplied the area around the artery passes in contact with the gland. opening of the parotid gland and the skin As the glandular branch is derived an- in its vicinity, and distal twigs supplied teriorly when the facial crosses superior the skin of the maxilla as mentioned to the submandibular duct, it arrives at above (Fig. 28). the glandular body after making a .0- 11. Angular branch of the mouth curve around the duct. Accordingly, Further descriptions are not given here various courses for it have been seen as since detailed observations were made by described by Takashima. Hanai. (1964). The styloglossal, the pterygoid and the 12. Superior labial artery digastric branches, and small twigs to the Further descriptions are not given here oral mucosa, were reported as muscular since detailed observations were made by branches by Ellenberger and Baum (1891) Hanai (1964). and Miller et al. (1964). These branches were designated as the styloglossal and the pterygoid muscular branches and the submandibular glandular branches by the present author. They have complicated 64 M. Irifume

distribution territories and branching fea- ably small since the origin of the artery tures, sometimes arising in common with was located in the anteriormost sector of one another. Ellenberger and Baum the sublingual region. referred to them as the glandular In man, Sicher (1965) and Kamijo (1966) branches. Tsuji (1969) described two stated that when the sublingual was un- medial pterygoid branches of the facial developed or defective, branches of the artery in the dog, which may correspond submental artery perforated the mylo- to the pterygoid branches and those of hyoid and gave blood to the supply area the digastic of the facial or the submental of the sublingual artery. In his textbook, in the present paper. Spalteholz (1954) gave an illustration in Ellenberger and Baum (1891, 1943), Sis- which the submental cmmunicated with son and Grossmann (1953), Miller et al. the sublingual behind the genioglossal (1964) and Kato (1973) stated that the muscle. The features of both arteries in facial artery in the dog sent off the sub- man resemble those of the corresponding lingual, which gave rise to the submental arteries in the dog. Branches of the sub- artery. However, Nickel et al. (1976) in mental in man communicate with the their book on the comparative anatomy sublingual behind the genioglossal muscle, of domestic animals, stated that in the and if the sublingual does not arise from dog the facial sent off the submental, the lingual artery, the sublingual will be which gave rise to the sublingual. almost equal in branching features to the The present author agrees with Nickel's vessel in the dog. description for the following reasons. 1) The communications between the sub- The submental artery (which was des- lingual and the submental arteries of both cribed as the sublingual artery by all the sides were grouped into ten types in the above authors except Nickel et al.) is present paper, comprising the so-called. derived from the facial, and the main sublingual arterial loop. Direct communi- stream is directed to the submental area. cation between the submental arteries of 2) The course of the artery lies ventral both sides or through the sublingual to the mylohyoid muscle. If the artery artery out of them right behind the sym- were to be designated as the sublingual, physis, was seen in 25 cases (i. e. about it should lie dorsal to the muscle in 63%). company with the submandibular duct. The peripheries of the inferior alveolar Such a vessel arising from the submental artery did not supply the symphysis in as described in the present paper is seen the dog, as described previously by Mizu- as branches of the mylohyoid branch tani (1977). However, it was noted that which perforate the muscle and supply the symphysis was supplied by a branch the submandibular duct, the sublingual out of the above-mentioned loop. This gland and the lingual gingivae, while a branch penetrates the symphysis and an- vessel which arises from the submental astomoses with the (periosteal) branch of artery in the anterolateral end of the the anterior mental artery and the genio- mylohyoid muscle, passes anterosuperiorly hyoid branch of the submental artery. around the posterior end of the origin of However, in cases where the loop is not the genioglossal and supplies a limited formed, the left submental artery pene- area covered with the sublingual artery, trates the symphysis. Sisson and Gross- is also seen. The present author there- mann (1953) and Miller et al. (1964) noted fore terms the vessel the sublingual ar- that the facialis gave rise to the inferior tery. The area, however, was consider- labial, the oral angular and the superior The Facial Artery of the Dog 65 labial arteries in the face. Ellenberger tani (1977), expands its supply area to et al. (1891) and Nickel et al. (1976) stated behind the middle mental foramen, the that the digastric and the masseteric lower third premolar when the posterior branches left the facial artery prior to mental artery is not developed, but the the origins of three above-mentioned area anterior to it is supplied by the arteries. Fujiwara (1970) reported that mental artery. the facial sent off one to five masseteric Regarding the superior labial artery branches in the dog, and grouped them (the posterior superior labial artery of into proximalmost, middle and distalmost Hanai 1964) and the oral angular artery, branches. Suzuki (1977) indicated that excellent descriptions have been given by several masseteric branches arose from Hanai. The present findings were essen- the facial and supplied all layers of the tially similar. masseter muscle in the dog. The former An accessory inferior alveolar artery (by Fujiwara) was termed the inferior was noted in the present study as an oc- masseteric branch by the present author, casional variation of the branching of the the middle the anterior masseteric, and facial artery. The usual inferior alveolar the last the masseteric of the buccal artery was not developed in such cases. branch. Finally, the relation between the sub- Ellenberger and Baum (1891), Miller et mental and sublingual arteries will be al. (1964) and Miyata (1966) stated that briefly discussed. Ellenberger and Baum the facial artery sent off the submandi- stated that the a. maxillaris externa of bular lymphnodular branch after giving the dog divided into the sublingualis and off the submental artery. In the present the facialis, and when the sublingualis study, the lymphnodular branches were reached the mental area, it was called found to arise from the inferior mas- the submentalis. Nickel et al. (1976) stated seteric, the cutaneous and the mandibular that the facial artery gave rise to the marginal branches. The inferior mas- submental artery, which gave off the seteric branch of the present author sup- sublingual artery in the dog. In textbooks plied blood to the intermediate and deep on human anatomy, the branches of the layers of the masseter muscle from its facial artery have usually been grouped anterior margin, differing from the r. into cervical and facial branches accord- premassetericus of Adachi (1928). ing to the areas of origin and supply. The buccal branch anastomoses with The nomenclature of the aa. maxillares the buccal artery as described by Hata externa et interna in man which had (1967), and simultaneously supplies the formerly been used in BNA, was also intermediate and deep layers. The mandi- used in the dog by Ellenberger et al. at bular marginal branch supplies the skin that time. The present author is greatly and some of the muscle, without dividing interested in the nomenclature of the into superficial and deep branches. The vessels, but such classic nomina were not superior labial artery and the oral angular used for the dog in the present paper, branch, as mentioned by Hanai (1964), although the peripheries of the sublingual divide into the superficial branch supply- artery of the submental artery from the ing the skin and the deep branch supply- facial artery were distributed to the an- ing the mucosa , respectively. The inferior terior part of the floor of the mouth for labial artery also divides into the branches the defective of the sublingual out of the mentioned by Hanai (1964) on the superior lingual artery. The author favors the labial. The artery, as indicated by Mizu- nomenclature of Nickel et al. 66 M. Irifume

The author wishes to express his sincere 11) Miyata, T. : Stereological studies on thanks to Professor Y. Ohta for critically several ducts and vessels by injection reading the manuscript, and to Assistant method of acrylic resin. XVI. Arterial Professor T. Tokioka and the staff mem- distribution of the submandibular lymph nodes in some mammals. Okajimas Fol. bers of the Department of Anatomy for anat. jap., 42 : 265-280, 1966. their invaluable assistance. 12) Mizutani, M. : On the mental arteries and lower incisor branch of the dog. Okajimas Fol. anat. jap. 53 : 359-382, 1977. Literatured Cited 13) Nickel, R., A. Schummer & E. Seiferle : 1) Adachi, B.: Das Arteriensystem der Lehrbuch der Anatomie der Haustiere. Japaner. Maruzen, Kyoto, Bd. 1, 73-80, Berlin & Hamburg, Bd. III., 108-115, 1928. 1976. 2) Arai, M.: On the a. malaris of the dog. 14) Okano, H. Stereological studies on Okajimas Fol. anat. jap., 54 : 361-376, several ducts and vessels by injection. 1978. method of acrylic resin. VII. On the ra.- 3) Ellenberger, W. & H. Baum : Systema- mification of A. lingualis and its fine dis- tische und topographische Anatomie des tribution in some mammals. Okajimas Hundes. Paul Parey, Berlin, 376-386, Fol. anat. jap., 34: 233-297, 1960. 1891. 15) Sicher, H.: Oral anatomy. C. V. Mosby, 4) Ellenberger, W. & H. Baum : Handbuch St. Louis, 328-333, 451-460, 1965. d. vergleichenden Anatomie d. Haustiere. 16) Sisson, S. & J. D. Grossman. : The an- 18 Aufl., Springer-Verlag, Berlin, 635-638, atomy of the domestic animals. 4th ed., 1943. Saunders, Phila., 766, 767, 1953. 5) Fujiwara, I.: Stereological studies on 17) Spalteholz, W.: Handatlas der Anatomie several ducts and vessels by injection des Menschen. Scheltema & Holkema method of acrylic resin. XXVII. Arterial N. V., Teil II, Bd. I, Fig. 806 Teil II, distribution of the masseter muscle in 219, 1954. some mammals. Okajimas Fol. anat. jap., 18) Suwa. F., S. Tominaga & H. Kumagai. : 47: 335-352, 1970. On the posterior deep temporal artery 6) Hanai, H.: stereological studies on of the dog. Okajimas Fol. anat. jap., 55 : several ducts and vessels by injection 255-264, 1978. method of acrylic resin. XIII. Arterial 19) Suzuki, T.: On the arterial supply of distribution of the upper lip in some the masseter muscle in the dog and cat. mammals. Okajimas Fol. anat. jap., 40 : Acta Anat. Nippon., 52: 299-308, 1977. 81-128, 1964. (in Japanese) 7) Hata, Y.: Stereological studies on several 20) Takashima, T.: Stereological studies on ducts and vessels by injection method of several ducts and vessels by injection acrylic resin. XVIII. On the buccal method of acrylic resin. XIX. Arterial artery in some mammals. Okajimas Fol. distribution of the submandibular gland anat. jap., 43: 331-361, 1967. in some mammals. Okajimas Fol. anat. 8) Kami jo, Y.: Oral anatomy, III. Angio- jap., 43 : 363-383, 1967. logy, 1st ed., Anatom, Tokyo, 455-470, 21) Taniguchi, Y., Y. Ohta & S. Tajiri. : 1966. (in Japanese) New improved method for injection of 9) Kato, Y.: Atlas of veterinary compara- acrylic resin. Okajimas Fol. anat. jap., tive anatomy. Vol. I, 50 & Vol. II, 438, 24: 259-267, 1952. 8th ed., Yohkendo, Tokyo, 1973. (in Jap- 22) Taniguchi, Y., Y. Ohta, S. Tajiri, H. anese) Okano & H. Hanai. : Supplement to new 10) Miller, M. E., C. C. Christensen & H. E. improved method for injection of acrylic Evans : Anatomy of the dog. Saunders, resin. Okajimas Fol. anat. jap., 27: 401- Phila. & London, 294-302, 1964, 406, 1955. The Facial Artery of the Dog

23) Tsuji, T.: Stereological studies on 24) Yoshikawa T., T. Suzuki, R. Kiuchi & several ducts and vessels by injection H. Matsuura : The comparative anatomy method of acrylic resin. XXII. Arterial of the musculus masseter of the mam- distribution of the medial pterygoid mals. Acta Anat. Nippon., 36: 53-71, muscle in some mammals. Okajimas Fol. 1961. (in Japanese) anat. jap., 46 : 21-40, 1969.

Key to Abbreviations and Explanation of Figures

Dig Digastric muscle Gng Genioglossal muscle Gnh Geniohyoid muscle Mas Masseter muscle Mpt Medial pterygoid muscle Myh Mylohyoid muscle Sig Sublingual gland Smd Submandibular glandular duct Smg Submandibular gland Sty Styloglossal muscle

am Anterior masseteric branch an Angular branch of the mouth as Ascending branch bu Buccal artery di Digastric branch of the submental artery ec External carotid artery fa Facial artery im Inferior masseteric branch in Inferior labial artery ii Lingual artery mh Mylohyoid branch of the submental artery mm Mandibular marginal branch pt Pterygoid branch sg Submandibular glandular branch sl Sublingual artery sm Submental artery St Styloglossal branch of the facial artery su Superior labial artery Direction of the snout S

Plate I

Fig.1. Inferolateral view of the submandibular region of the right side・ ×C・2・0・

The submandibular gl鋤d and the venter and insertion(dotted line>of the digastric muscle were removed. The facial artery arises anteriorly from the extemal carotid between the stylo910ssal and the digastric, anterior to the bulla tympan圭ca (*). It gives rise to the submental artery撫t the posterolateral end(/>of the mylohyoid muscle and comes to the face via the vascular notch。 The hypoglossal nerve(○)is accomp鋤ied by the lingual artery. Fig.2. Inferior view of the submandibular region of the right side・ xC・L7・ The facial artery arises from the external carotid anteriorly when it be簸ds superolaterally along the upPer margin of the digastric, and gives rise to the styloglossal and the sub・

mandibular glandular branches, superomedial to the digastric. The glandular branch makes aU・curve posterolaterally towards the hilus, a蝕d en roUte sends twigs(/)to the sub. mandibular duct and the sublingual gland. The pterygoid bran¢h arises from the artery •-•,,2. C which crosses above the duct and supplies the insertion of the medial pterygoid muscle。 8 CD Fig。3. Inferolateral view of the retromandibular region of the right side. xC.2。2・

The facial artery is derived from the external carotid right proximal to the terminal divi・ sion of the superficial temporal (率) and the maxillary (**〉, and sends off the inferior masseteric(○)and the pterygoid branches。 The submental artery in this case arises direct1y from the extemal carotid and gives rise to the styloglossal, the submandlbular glandular and the pterygoid branches, and a small twig(→)leaves the artery where the usual facial a就ery comes to the face and supPlies the digastric。 The transverse facial 〈x) arises from、 the superficial temporal and supPlies the usual area. Fig.4。 Inferolateral v三ew of the left side. xC。0。8. The mandibu1ar ramus and the Iateral wall of the mandibular canal were removed. An

accessory infer董or alveolar artery(←)arises from the facial artery, but the usual inferior alveolar(○)arising from the maxillary, which is丘ne, supPlies the first and second mo1ar teeth only. 69

Plate I

\l. Irifune Plate II C

Fig.5. Anterolateral view of the facial argery in the submandibular region of the left side . ×C.5。0.

The common trunk(○)between the submandibular glandular and the styloglossal branches

is derived from the facial 〈cut off along the dotted line),and the glandular branch supplks

asmall twig(ゆ)to the submandibular duct and the sublingual gland. Fig,6。 Lateral view of the origin of the facial artery of the left side . ×C.3.O、

The styloglossal branch(↓)arises from the external carotid directly in this case。 The

submandibular branch supplies the gland after making a U・curve.

Fig。7. Inferolateral view of the submandibular region of the right side . ×C.2.3.

The styloglossal branch gives off a twig(←)to the digastric muscle(absent in this figure/

and the submandibular branch gives off a twig(○)to the submandibular duct and the sublingual 91and. Fig・8・Medial view of the insertion(broken line)of the medial pterygoid muscle◎f thc r噛ht

side。 xC.2.3.

The submandibular glandular branch arises in common with(↑)the pterygoid branch when it makes a U-curve around the duct.

Fig。9. Inferolateral view of the submandibular regi◎n of the I£ft side. xC .1、0.

C The submental artery gives rise to the common trunk(/)between the submandibωar

glandular and the digastric branches。 The glandular branch runs posteriorly Iateral to the fD

ducらand en route gives off twigs to the sublingual gland and the submandibular duct(○)、 Fig.10. Medial surface of the mandible of the Ieft side . ×C. L6.

The pterygoid branch gives off a twig(○)to the oral mucosa and a twig(x)to the sublingual gland and submandibular duct.

Fig.11. Superomedial view of the mylohy◎ld muscle of the right side . xC.1.4.

The facial artery gives rise to a common trunk(↓)between the small twigs to the oraI

mucosa(○)and the sublingual gland(x)after giving off the pterygoid branch。 The

my1Qhyoid branch of the submental artery perforates the muscle and supplies the sublingua1

gland and submandibular duct, anast◎mosing with twigs to the sublingual gland. Twi幕s to

the oral mucosa anastomose with the peripheries of the lingual branch on the anteri◎r

margin of the medial pterygoid muscle.

Flg.12. Inferomedial view of the origin of the submental artery of the right side, xC.3 。7.

The insertion Qf the medial pterygoid muscle is indicated by the broken line. The facla1

artery sends off the pterygoid branch and a twig(○)to the oral mucosa, anasしQmosing

with the lingual br葺nch(×>at the anterior margin of the medial pterygoid muscie. The

submandibular glandular branch arises fr◎m the submental artery、 71

Plate II

M. Irifune Plate III I

Fig.13. Similar area to tigure 12 but from the left side, showing the styl◎gl◎ssal branch of th¢

facial artery and twig曳 ← ・)to the muscle from the pterygoid branch. ×C、3.3.

Fig.14. Inferior view of the submandibular region of the l¢ft side, ×C. L3、

The insertion(dotted line)of the digastric muscle was rem◎ved. The submental artcry

runs anteriorly and slightly medially Gn the medial surface of the mandible togαher with

the mylohyoid nerve (↑).

Fig.15. Lateralview of the submandibωar region of the left side. xC.0。6,

The whole rami丘cation of the submental artery was picked up from the鋤bmandibular

region. The artery runs anteriorly beneath the mylohyoid muscle, giving off the digastric inferiorly and the mylohyoid branches superlorly(mh*)and medially(mh),and serds cff

the sublingual artery at the posterior end of the origi簸of the genioglossal muscle・

Fig。16. Lateral view of the submandibular region of the left side. ×C、1。0、

The mandible was removed to show the orlgin(broken line)of the mylGhyold muscle and

the lower lingual gingivae。 The mylohyoid branches supply the◎rigin a獄d perforate it

(○)to supply the gingivae, anastomosing with the lingual branch(*). The digastric

branches supPly the muscle and the mylohyoid・ 1,•• Fig.17. Close・up of the anterior part◎f丘gure 16・ ×C・L6・

The submental artery runs anteromedially beneath the◎rigins of the genioglossal and the

CD geni◎hyoid(broken line)towards the symphysis, aDd the geniohyoid bronch consists of tlle

medial(△)and superior(△ △)branches, The artery anastomo$es with its cpPosite fellow

(○)and the sublingual artery(→)of the$ame side, forming a sublingual arterial lo◎p of

type VIL When the sublingual artery runs medially above the origins of the gmio910ssal

and geniohyoid musclcs, it gives o」ff the gingiva1 (*> and the genieglossa1 (x> branchcs・

Fig.18. Median section of the mental region of the left side・ ×C・1・6・

The submental artery gives off the sublingual artery superoanteriorly at the post¢rior end

of the origin of the genio910ssal muscle・ The sublingual artery runs anteromedially above

the genioglossal and geniohyoid(broken line)muscles along the submandibular duct・giving

off the genio910ssal(×)and glngiva1(○)branches・ The sublingual artery anastom◎ses

with the submental artery at the anterior end of the geni◎hyoid, and the submenta!artery

anastomoses wlth its opposite fellow, f◎rming a sublingual arterial loop of type IIL Twi葺s

(*)arising from this loop supply the symphysis(dotted line)。

Fig。19. Inferolateral view of the submandibωar region of the left side・ ×C・L9・

The facial artery(x)and the mandible were removed. When the submental artery passes

above the insertion of the digastric, it gives off the digastric branch which supPlies the

platysma and the medial pterygoid muscle、 73

Plate III

\I. Irifune - ..;-.

Plate IV

Fi鼠.20. Superomedial view of the upPer surface of the my1Qhyoid muscle of the riμht side・

xC.1、6.

The tongue was removed(the median line is indicated by a white line)・ Thc twig to the

sublingual gland(x>of the twig(↑)to its oral mucosa, the mylohyoid of the submental

and the genioglossal (○) branches of the sublingual, pass alon宮 the submandibular duct・

anastomosing with their adjacent fellows. Fig.21. Inferior vlew of the submandibular region. xC. L4.

The mylohyoid branch of the submental artery runs media}ly beneath the muscle and an-

astomoses with the branch(○>to the inferi◎r of the lingual artery and branches of the

geniohyoid. Fig.22。 Inferior view of the submaPdibular region. ×C.0.5,

The cutaneous branches in this region are shown。 The mylohyoid branch of the submental *--, perforates the muscle to the skin and anastomoses with its oPPosite fellow and the cuし 1,^•I --1 aReous branches of the submental(○)and mental(×)arteries. 1.^•• Fig.23. Superior view of the floor of the mouth. ×C.1.2, c 9 The tongue and capillary plexus◎f the lingual gingivae were removed・ Genioglossal CD

branchesの1eave the sublingual medially and supPly the genio910ssal and the geniohyoid・

Gingival branches(←)pass beyond the interdental papillae and anastomose wlth gingival

branches of the menta!arteries. The anteriormost(○)of the them, which is thick, sup-

plies the gingivae anterior to the first premolar tooth. The sublingual artery anastomoses

with its opposite feUow above the origin of the geniohyoid muscle(between the broken

lines). A twig(x)arising from the Ioop(type I)supplies the symphysis. Fig.24. Lateral view of the mental region of the right side. xC. L2、

The mandible was removed. Athick gingival branch(○)arises from the submental artery・

Fine gingival branches(×)and the sublingual plical branch(瀕>arise directly from the

sublingual artery. The upper margin of the sublingual plica is indicated by the broken line.

Fig.25. Lateral view of the submandibular region of the left side・ ×C・3・8・

The mandibte and glngivae were removed. The genioglossal branch(○>of the sublingual

artery supplies the m疑scle(↓),the submandibular duct and the sublingual plica(× 、. 75

Plate IV

M. Irifune Plate V - , Fig・26・Median section of the symphysis of the 1¢ft side xC CT, . L9.

△b「anch(x)・f the sublingual arterial l・・P(○)runs anteri・rly in the symphysis t。 supPly 叢t・ぞnd apast・m・ses with the peri・steal branch・f the anteri・r mental a rtery(Dand the gem・hy・b 叢d bmnch・f the submenta1(△)i鈍the 1・wer lip(*), but n。 しwith the incisive ranch of the inferior a正veolar artery . F蓋9・27・lnfer・lateral view・f the submandibular regi・n。f the left side . xC. L9,

Immゆte1Y bef・re the facial artery c・mes t・the face, it gives・ 鉦the inferi。r masseteric, the d1gastnc (○) and the cutaneous (×) branches. Fig・28・Infer・lateral view・f the face and the submandlbular regi。n。f the left side . xC.0.5.

The b.ranch t・the superi・r・f the facial artery anast・m・ses wlth vari。us cutane。us branches, Le・those of the fタcial arising at the mandibular basis(D b ,・f the mandlbular maゆal 「anch(x)・ ・f the lnferi・r labial(○ 〉・ ・f the superi・r thyr・id(△),。f the myl。hy◎id

b「anch(×x>・f the submenta1・ ・f the malar artery(・)and the lateral palpebral artery (○ ○)of the superficial temporal. Fig.29。 Lateral view of the buccal region of the right side . xC.1.6、

. ..., The th facial artery gives・ 仔the cutane・us branch, the mandibular marginal branch(_>and ._. e anteri。r masseteric bra簸ches・in that◎rder ・The middle branch supPlles twigs(○)t。 . the submandibular lymph n・des, a勲d the latter branches(tw・in number>arise iR c。mm。n .:-.4 with the bu£cal branch which anast・m・ses wlth the buccal artery at the a = nteri・r margin a ・fthe mandlbular ramus・The inferi・r labial artery and the angular branch。f the m。 CD di uth vide int・the superficial(×)and deep(×x)branches , respectively. The branch t。 the

supe「io「a「lres fr・m the superi・r labial artery and supPlies twigs t・the par・tid duct ・・), and beyond lt extends t◎the aRterior surface of the zygomatic bone . Fig.30。 Lateral view of the buccal region of the right side . ×C.0.9.

The anteri・r masseteric branch anast・m・ses with the branch(x)t。 the inferi。r。f the masseteric branch(△)・f the transverse facial artery. The buccal branch arises fr。m the

§uprlo「lapial artery and anast・m・ses with the peripheries(/)・f the buccal artery. The lnfer1・r lablal artery arises in c・mm・n with the angular braRch・f the m。uth , and b。th vessels divide int・superficial(○)and deep(○ ○>branches , respectively. A smaH twig

.(*)in c・mpany with the inferi・r labial vein arises fr・m the inferi・r labial artery. -F lg。31. Lateral view of the face of the right side . xC.0.9.

The (○) inferi・r labial artery and the a・gular branch。f the m・uth divide int。 the superficial and deep(×)branches, respectively , anast。m・sing with。ne an。ther. The inferi。r

labial ∫ artery anast・m・ses with the inferi・r labial branch・f the p。steri。r(。)and the mlddle **)mental arteries・and the superi・r labial anast・m・ses with the peripheries(△) 。f the lnfraorbital artery and of the angular branch of the mouth. 77

Plate V

M. Irifune