ANTARCTIC ZOOGEOGRAPHY 36 1 



expansion into cold-water areas. He also rightly regards the absence 

 of connectants through the warmer regions as of more importance 

 than absolute identity of the bipolar forms. It should be noted by 

 way of caution, however, that Meisenheimer deals for the most part 

 with rather widely distributed north temperate, rather than with truly 

 Arctic or sub-Arctic pteropods. 



Pelseneer,^^ Dollo,^^ and Regan^^ have, on the other hand, strength- 

 ened the objections of Thompson. Dollo, for example, states that 

 evidence drawn from the fishes, birds, mammals, tunicates, crusta- 

 ceans, mollusks, worms, echinoderms, coelenterates, sponges, and 

 plants, is all against bipolarity. He holds that the polar faunas are 

 independent adaptations and in no sense the relics of a universal 

 fauna spreading toward the poles from tropical shallow water or mud 

 line. The existence of certain identical and non-cosmopolitan or- 

 ganisms in both polar areas is not impossible, he admits, but is aside 

 from the problem. The real point concerns the question as to whether 

 the characteristics of the present polar faunas are due to a direct 

 common origin and whether they have remained unchanged because 

 of the maintenance of polar climates. 



Gran,^^ in a work by Murray himself, mentions two species of 

 oceanic diatoms which are "the two most characteristic forms along 

 both the polar boundaries of the Atlantic." He adds, however, that 

 these forms have both been found within the tropics and that there 

 is no similar agreement between the Arctic and Antarctic waters 

 when we consider the neritic diatoms. 



ggj.j-yi9 states that the cephalopod fauna of Antarctic shores 

 shows no relation to that of the Arctic save a superficial facies due, no 

 doubt, to the similarity of physical environment. There is not a single 

 bipolar species. 



Ortmann^'^ stresses the peculiar character of much of the south 

 polar fauna. He believes that little if any of it is derived from the 

 tropics but that it is rather a remnant of the Pacific Mesozoic fauna 

 which had its original home on the shore of the Antarctic Continent. 

 A rather extensive and striking element which he finds among the 

 littoral ensemble at the southern extremities of the great continents 



15 Paul Pelseneer: Mollusques (Expedition Antarctique Beige: Resultats du Voyage du S. Y. 

 Belgica en 1897, 1898, 1899 sous le commandement de A. de Gerlache de Gomery: Rapports Scienti- 

 fiques, Vol. 7-9: Zoologie, Part 50-51, P- S8), Antwerp, 1903. 



16 Louis Dollo: Poissons, ibid.. Vol. 7-9, Zoologie, Part 53, Paris, 1902, section on " Bipolarite," 

 pp. 191-207. 



1' C. T. Regan: The Antarctic Fishes . . . (Scottish National Antarctic Expedition: Report 

 on the Scientific Results of the Voyage of S. Y. "Scotia" . . . 1902-1904, under the leadership 

 of W. S. Bruce, Vol. 4: Zoology, pp. 311-374), Edinburgh, 1913- 



18 H. H. Gran: Pelagic Plant Life, in: Murray and Hjort's "The Depths of the Ocean," London, 

 1912, pp. 307-386; reference on p. 352. 



19 S. S. Berry: Cephalopoda (Australasian Antarctic Expedition 1911-1914, Scientific Repts., 

 Ser. C: Zoology and Botany, Vol. 4, Part II, pp. 1-38), Sydney, I9i7- 



2" A. E. Ortmann: Origin of the Deep-Sea Fauna, Rept. 8th Internatl. Geogr. Congr., Held in the 

 United States, IQ04, Washington, 1905, pp. 618-620. 



