Pollen morphologyof the Alangiaceae Tj. Reitsma Division of Palaeobotany and Pollen Morphology, Botanical Museum and Herbarium, State University, Utrecht (The Netherlands) (Received July 24, 1970) SUMMARY This of paper presents a pollen-morphological study Alangium, a genus mainly restricted to the tropics of the Old World, of which 18 of the 19 known species were studied. The pollen grains, studied with the use of a light microscope, a transmission electron microscope and a scanning electron microscope, were classified into 15 pollen types, to which a key is given. Comparison of fossil and recent grains produced some information about both the evolutionary trends in the characters of the pollen grains and the phytogeography of Alangium. INTRODUCTION Alangium, the only member of the Alangiaceae, occurs in Africa, India, Pacific islands. of sometimes China, Japan, Malaysiaandin some Itisagenus trees, or shrubs or woody climbers, which occur from sea level to 3,300 m above sea level. The importance of Alangium lies in the fact that this genus is found in Tertiary sediments, mostly outside the present area (e.g., Traverse, 1955; Krutzsch, 1962, 1969). Because no agreement exists about the relationship of the fossil pollen grains to the recent ones, it seemed useful to make a comprehensive study of the recent pollen grains, the more so as a comparison of fossil and recent pollen grains can provide some information about the evolution of the characters. For this reason it was necessary to study pollen grains of various specimens collected in different in order to obtain of the of the features in areas a survey variability recent pollen grains. Since the identification of the specimens used is not always correct, it is that studies should be done in necessary pollen-morphological cooperation with an expert in taxonomy, or with the help of a recent monograph. Otherwise pollen- morphological studies lose their value, as the results are not always reliable. Fortunately Bloembergen (1939) presented an excellent monograph of the It is clear that the could have been undertaken Alangiaceae. present study not without this monograph at hand. Rev. Palaeohotan. Palynol., 10 (1970) 249-332 249 METHODS AND EQUIPMENT Light microscopy Pollen grains of Alangium were obtained from herbarium material, from These which the anthers had just opened. anthers were isolated with the use of Afterwards the anthers and wetting agent. were ground through a sieve ace- tolysed (for detailed description see Reitsma, 1969). The acetolysed pollen grains were mounted in glycerin jelly. Granules of modelling clay were used in order to prevent large pollen grains from being compressed. Pollen grains were examined with a Leitz Ortholux microscope (obj. pi. apo ol 100/1.32,oc. periplan GF 10 x). Photomicrographs were made with the Leitz use of a Leitz Orthomat and a Ortholux microscope (obj. apo 40/0.65 and FI ol 70/1.30). Transmission electron microscopy Acetolysed pollen grains were concentrated into pellets by agar embedding (Rowley, 1959). These pellets were cut into small cubes by means of a razor blade. The agar-exine cubes were dehydrated and then embedded in Epon 812. Thin sections were cut with a LKB-microtome and examined with the use of a Philips EM-100 electron microscope. The electron-microscopical investigations were carried out in the Depart- ment of Electron Microscopy of the Catholic University at Nijmegen (head: Dr. M. M. A. Sassen). Scanning electron microscopy Pollen grains were rinsed in 100% alcohol immediately after treatment in acetolysis mixture. The pollen grains, stored in 100% alcohol, were fixed to holders and then coated under with thin film of specimen high vacuum a very coal and gold (100 A C, 500 A Au). The pollen grains were studied with a Cam- bridge Stereoscan MK Ha scanning electron microscope. The scanning-electron-microscopical investigations were carried out in the Institute of Medical Physics of the University of Munster, Germany. MATERIAL Herbarium material from the following herbaria was used in this study. BO Bogor (Indonesia): Herbarium Bogoriense, Lembaga Biologi Nasional. BR Bruxelles (Belgium): Jardin Botanique de 1’Etat. K Kew (Great Britain): Royal Botanic Garden, The Herbarium and Library. 250 Rev. Palaeobotan. Palynol., 10 (1970) 249-332 L Leiden (The Netherlands): Rijksherbarium. NY New York (N.Y., U.S.A.): The New York Botanical Garden. P Paris (France); Museum National d’Histoire Naturelle, Laboratoire de Phanerogamic. S Stockholm (Sweden): Naturhistoriska Riksmuseet, Botanical Department. U Utrecht (The Netherlands): Botanical Museum and Herbarium. WAG Wageningen (The Netherlands): Laboratory of Plant Taxonomy and Plant Geography. The author is indebted to the directors, keepers and curators of the above mentioned herbaria for the loan of herbarium specimens. As rule the of from has been a use pollen type-material avoided, except in the case of A. brachyanthum, as only a single specimen is known from this all of the examined. species. As far as possible known species genus Alangium were listed of in his excellent Bloembergen (1939) eighteen species Alangium mono- graph of the genus. Threefurther species have been described since Bloembergen’s monograph appeared. According to Eyde (1968) two of these, A. chungii Li and A. tonkinense Gagnepain, are conspecific with A. salviifolium and A. kurzii, The third be respectively. species, A. griseolloides Capuron, appears to a good species. Therefore, the genus Alangium includes 19 species, of which 18 have been hirsutum studied. It was not possible to study pollen grains of A. Bloembergen, because the single specimen known from this species was not present at the Rijks- herbarium of Leiden (The Netherlands), although Bloembergen (1939) cites a Bornean specimen, Hallier B.3238, from the Rijksherbarium. Bloembergen (1939) classified the species into four sections. According to Capuron (1962) A. griseolloides, the only species not mentioned by Bloem- bergen, belongs to section Conostigma. I have followed Bloembergen’s delimitation of the taxa and I have also adhered to his nomenclature and orthography, with a few exceptions, in order to bring them into harmony with the International Code of Botanical Nomenclature (1966). According to Article 22 of this Code, section Angolum Baillon, which includes the type species of Alangium, must be renamed section Alangium. According to Article 26 the names of the following includes the nomenclatural subspecies must be altered, because the subspecies type of the Wangerin Wan- species: A. salviifolium (L.) ssp. decapetalum (Lamarck) gerin must be changed into A. salviifolium (L.) Wangerin ssp. salviifolium; A. villosum (Blume) Wangerin ssp. salaccense (Koorders et Valeton) Bloem- villosum. bergen has to be changed into A. villosum (Blume) Wangerin ssp. article is also relevant villosum Wangerin The same to A. (Blume) ssp. tomentosum (Von Mueller) Bloembergen var. australe Bloembergen. This name has to be altered into A. villosum (Blume) Wangerin ssp. tomentosum (Von Mueller) Bloembergen var. tomentosum. According to Recommendation 73G the specific epithet salvifolium is spelled salviifolium. 251 Rev. Palaeobotan. Palynol., 10 (1970) 249-332 SPECIMENS EXAMINED Alangium Lamarck Section Alangium A. brachyanthum Merrill —Luzon: Forestry Bureau 10341 Curran (NY, isotype). longiflorum A. Merrill —Luzon: Alberto 326 (U), Forestry Bureau 14773 Darling (BO, northern Borneo; Aban Gibot SAN isotype); 30390 (L); Moluccas: Main and Aden 1465 (L, BO). A. Wangerin salviifolium (L) ssp. salviifolium—Kenya: Kenya Forestry Department Dale 3763 (K); Tanzania: Semsei 977 (K); India, Malabar: Stocks, Law s.n. (NY); southern India: Ekambaran and Janaki 1062 s.n, (NY), Wight (NY) Wight 1063 (NY), Wight 1256 (L), Yeshoda 332 (NY); Hainan: Hancock 35 (K), Liang 65366 (NY), How 70323 (K), How 71319 (S); North Vietnam: Petelot 6386 Thailand: Garrett (NY); 1075 (L), Royal Forest Department 88 (NY); South Vietnam: Pierre 5157 (NY), Pierre 9179 (NY). A. salviifolium (L) Wangerin ssp. sundanum (Miquel) Bloembergen —India, Malabar Coast: coll. s.c. s.n. 20-5-20 (S), Wight 1064 (NY), Wight 1255 (L); India, Mysore: Hohenacker 700 Walker (U); Ceylon: s.c. s.n. (P), s.n. (P), Walker 38 (K), Wight 1254 (K); Andaman Islands: Parkinson 540 (K); Sumatra: Achmad 399 (L); Java: Bogor Botanic Garden XVII-C-136 (L), s.c. s.n. 043707 H.B. (U), Zollinger 2289 (L); Sumba: Teysman s.n. (L); Celebes: Teysman 13832 (L); New Guinea: Pleyte 1034 (L), Zippelius 197c (L). Section Conostigma Bloembergen A. Capuron griseolloides —Madagascar; Service Forestier de Madagascar 25752 S.F. (P). A. havilandii Bloembergen —Borneo, Sarawak; Anderson 12868 (L, BO), Sanusi bin Tahir 9218 (L). A. Wangerin— Griffith javanicum (Blume) Malaya: 3383 (U), Henderson 28980 (BO), coll. King’s s.n. (L), Maingay 706 (L); Sumatra: Achmad 1266 (L); Bangka: Kostermans and Anta 1152 Java; Blume 7529 (L); (L); Borneo, Sabah: Ampuria 36521 (L), Elmer 21165 (L, S), Kostermans 4365 (L), Mikil 41761 (L), Muin Chai SAN 26904 (L), Wood SAN 15084 (L), Wood and 15400 Charington (L); Borneo, Sarawak: Havilland and Hose 2885 (L), Jacobs 5359 (L); Nunukan Island: Paymans 180 (L); Brunei: Smythies and Ashton 5851 (L); Celebes: Boschpr. h.b. Cel/V/199 (L, BO); Philippine Islands, Luzon: Elmer 14782 (S, U), Forestry Bureau 2284 Mindoro: Edano 3245 Meyer (S, U); (L); Moluccas, Seram: Kuswata and Soepadmo 78 (L), Rutten 1832 (BO); New Guinea: Ledermann 9818 (L), Schram 9455 (L); Solomon Islands: Brass 3002 (L), Snijder 4461 (L), Van Royen 16421 (L), Walker and White 167 (L), Whitmore 768 (L), Whitmore 942 (L). A. maliliense Bloembergen— Celebes: Cel/V/161 (Waturandang 43) (BO, L). A. nobile (Clarke) Harms—Malaya: Griffith 3885 (U), King’s coll. 6116 (BO), King’s coll. 10892 (L); Sumatra: Bequin 582 (L), Boschpr. T.3.P.864 (L). A. ridleyi King—Malaya: Kochumen KF 99369 (L); Sumatra; Achmad 1297 (U), Boschpr. 131.T.3.P.369 (L), Boschpr. 160 E.l.P.852 Thorenaar (L); Borneo: Kostermans 10178 (BO), Sauveur 141 (L). Section Marlea Baillon 252 Rev.