THE DISTRIBUTION of the Proteacei®: PAST and PRESENT
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THE DISTRIBUTION OF THE PROTEACEi®: PAST AND PRESENT B y s . B. K a u sik , D.Sc. Department o f Botany, University o f Mysore Central College, Bangalore (With two maps and appendix) (Communicated by B. Sahni) Received for publication on January 8, 1943 I ntroduction T h e distribution of the Froteaceas at the present day in certain ■widely separated localities in the southern hemisphere is not only one of the most fascinating problems in plant geography, but is also such an intricate one that it has always evaded au explana tion which approaches finality. Similarly, much controversy also existed at one time with regard to the fossils ascribed to this family, and the opinions expressed by botanists were, therefore*, invariably conflicting. The fossil forms belonging to the Proteacese have been dealt with in the past by Unger, V. Bttingshausen, Hecr, Saporta and others, and also by several recent workers. Many of the earlier determinations, based on winged seeds and fruits, used to bo generally regarded as useless, for the view was often expressed that they prob ably belonged to entirely different families. For the same reason, several of the leaf impressions stated to belong to the Proteacea^ were also often viewed with a certain amount of scepticism, and very recently Gothari (1932) has also expressed doubts regarding the validity of the forms ascribed to this family. He remarks : “Es ist klar, dasa die Anwesenheit dieser Familie iiii europaischen Tertiar ein sehr wichtiges pflanzengeographisches Problem bietet; nach dem, was man Bonst von der Tertiarpflanzengemeinschaft weiss, ist dies nicht gerade wahrscheinlich.” However, Berry (1916), one of the leading American palseobotanists who has devoted a good deal of careful attention to this subject, has expressed that ‘‘though excep tion may justly be taken to some determinations of Unger, Ettings- liausen and Heer, these doubtful determinations in nowise affect the main body of facts ”, and has also further remarked that the “fossil forms are sufficient, after doubtful determinations are excluded, to show that the Proteaceae originated in the northern hemisphere, first appearing at the close of the Lower Cretaceous epoch and becoming practically cosmopolitan in the Upper Cretaceous time, when they reached the Australian region from south-eastern Asia.” Berry (1916) has reviewed the innumerable fossil forms of this family in a detailed account of the geological history of the family. These and also some additional forms which have since been described by several recent workers are mentioned in the following paper, and some interesting features in the distribution of the modern members are also pointed out. The paper, however, does not deal with any fresh or additional forms ; on the other hand, it is intended to give only a summary of our present knowledge of this subject. The F ossil H istory of the PaoTEACEiE In Europe the fossil Proteaceje are represented by a large mimber of Cretaceous and Tertiary forms found abundantly in various localities (Map 1 and appendix). These forma belong to the following genera, of which some are also known by living types in the southern hemisphere at the present time, while the others are strictly extinct types:—Protea and the allied generalized types Proteoides, Proteophyllum and Proteolepis, Genarrhencs, Helicia, Lambertia, Eakea, Knightites, Lomatia and the allied genus Loma- tites, Stenooarpus, Persoonia, Petrophiloidfis,^ Leucodcndrites, Orevillea, Embothrium and the closely related genus Emhothrites, Dryandra and the allied genus Bryandroides, Banksia and the related form Banksites, and lastly Boupala with the related genera Bho- palospermitee and Ehopalophyllum. In addition to these forms, some fresh ones have also been reported recently. Keid and Eeid (1915) have described the half of a hard fruit from the Plio(jene of Holland and state th at it is “so like that of Hakea, and so unlike anything else ” that it must be regarded as a new species of this genus. They further observe that this is perhaps the “ last representative of this dying out family in Europe ”. Principi (1919) has reported a species of Lomatia from the Oligocene of Italy, and very recently Velenovsky and Viniklar (1926-31) have recorded from the Cretaceous of Bohemia one species under each of the genera Dryandra, Conospermitea and Banksicarpns, and also a number of species under the generalized type Proteophyllum. They think that it is only probable that the forms referred to the genus Pro teophyllum belong to the Proteace®, but remark in the case of Banksicarpm, the determinations of wMch are based on inflores cences bearing round sessile fruits, that there are strong affinities with the well-known modem Australian genus Banksia. The fossil forms found in North America and which belong to the Cretaceous and Tertiary are represented by the genera * Bowerbank, in his classic study of the fossils from the Isle of Sbeppey, established the genus PetrophUoides from its supposed resemblance to the modern ProCeaceous genus Petrophila. Several species were referred to this, but one of these was subsequently shown by Starkie Gardner (1879) to be an Alnus, while some of the other species were referred to Sequoia by Ettingshauscn. However, Ettings- hausen (1879) retained Onally three English Eocene forms after a careful study of these fossils (Berry, 1916). Even these must now be regarded as useless, for Reid and Chandler (1933) have recently shown that, in ^eir fruit characters, they belong unmistakably to the Juglandace®, except one s ^ ie s, P. oviformis, which they place in the Lauracea. Palceodendron, two species of which are also fouud in the Atane beds of Greenland ; Proteophyllum, established by Fontaine, but regarded by Berry (1.916) as not being a trustworthy type; Gonospermites, deter mined by Fontaine and again regarded as useless ; Lomatia, of which the Miocene forms preserved in the volcanic ash at Florissant, Colo rado, are stated to he extremely convincing (Knowlton, 1926); Fer- soonia, Ernbothriopsis, Embothrites, recorded from the Dakota sand stone, but regarded as doubtful ; Dryandroides, Bankaia, includ ing an Alaskan (f) Eocene species and three well-marked species in the Wilcox flora; Enightiophyllum, and a probable Banksia fruit referred to the form genus Oarpolithus. Eecently, a new Eocene (middle or upper) species of Banksia from south-eastern North America (Berry, 1924) and a Cretaceous species of Dryandroides from Colorado (Brown, 1933) have also been reported. In Berry’s (1916) original account there is no mention of any fossil form from South America, but three forms have lately been reported by him from this continent also. These are a pre-Miocene species of Embothrites from Argentina (Berry, 1932), a Miocene species of Lomatia from Patagonia (Berry, 1934), and a Miocene species oi Guevina from Northern Patagonia (Berry, 1934). I t may be pointed out here that Lomatia and Oucvina are found in South America at the present time also, and further it seems to be signi ficant that Guevina is peculiar only to this continent even to-day and is not found anywhere else in the other Protead centres. lu the continent of Australia, where we have the largest number of the Proteaceai living at present, there are, by contrast, only a very few fossil forms. Tlie Cretaceous forms of these fossils belong to the genera Proteoides, Gonosper miles, Grevillea and Bhopalophyllum (V), and the Tertiary forms are an Oligocene species of Knightia, a few Oligocene (but more probably Miocene) species of Lomatia, one of which is also found in Tasmania, a Tertiary species of Per- soonia in New South Wales, an Oligocene species of Eoupala, and Oligocene or Miocene species of Dryandra, Dryandroides (in Tasmania) and Banksia. In the Antarctic continent three Oligocene species referred to the genera Knightia, Lomatia and Embothriophyllum are recorded from Grahamland. • Berry (1916) does not refer to any fossil Proteaceae in the continent of Asia, but a few forms are known from this region recently. Two of these are Cretaceous forms referred to the genera Proiecephyllum from Siberia (Kryshtofovieh, 1929) and Dryandra from south-eastern Trans-Caucasia (Palibin, 1930). With regard to the former, however, it has already been mentioned that it cannot be regarded as a trustworthy type. In addition, Kryshtofovieh (1929) has also referred some Tertiary fossils from Oligocene beds in Turkestan to the genus Dr^artdra; however, this determination has now been shown to be incorrect by Korovin (1932) on the evidence of additional material from the same locality showing axillary inflor- escenoes and thus bearing a strong affinity with the tribe GrevilleaB. 4o Korovin has, therefore, established a new genus Palibinia for these forms. We may now refer here to certain interesting facts in the dis tribution of the fossils belonging to this family. We find that several of these fossil genera are represented as common types to two or more regions, a fact which is in sharp contrast with what is seen with regard to the modern members. These fossil types are Lomatia in Europe. N orth and South America, Australia and Antarctica; Emboihriie^ in Europe and North arid South America ; Dryandra in Europe, Australia and Trans-Caucasia; Dryandroides in Europe, North America and Australia; Banksia in Europe, North America and Australia; Knightia in Australia, and the related forms Enightitea and Enightiophyllum in Europe and North America respectively ; Gonospennites in Europe, North America and Austra lia ; Qrevillea in Europe and Australia; Proteoides in Europe and Australia ; and Roupala and Rhopalophyllum in Europe and Austra lia. On the other hand, the living forms to which these fossils are most closely related are found to-day in distinct and far-sepa rated regions where they occur as purely endemic types, all in the southern hemisphere. There is also another interesting fact regarding the past and present distribution of certain members of this family.