194 



NATURE 



[June 26, 1890 



and lastly the Manchurian sub-region, which consists of 

 China and Japan. 



The scheme which represents, after Boulenger, the 

 distribution of Amphibia, strongly indicates their distri- 

 bution in parallel zones — namely, a northern, equatorial, 

 and southern zone. Australia is obviously American in 

 character, but the Indian region includes the whole of the 

 Malayan islands and even New Guinea. 



Palsearctic — Nearctic Region 



i. . I . . 



Ethiopian + Indian Region Neotropical Region 



+ 



Australian Region. 



Concerning fresh-water fishes, after Dr. Giinther, the 

 diagram shows at a glance that the form of the continents 

 has little influence upon the distribution. There are like- 

 wise parallel zones, one of which, the Arctic, contains no 

 fresh-water fishes. 



Northern Zone = Paloearctic + Nearctic Region. 

 Equatorial Zone — 



African + Indian Pacific or Australian -f- Neotropical Region 

 (Cyprinoid Section) (Acyprinoid Section) 

 Antarctic Zone = Tasmanian New Zealand Patagonian 

 -~ ^ -^ 



Sub-regions. 



The distribution of terrestrial mollusks is that of S. P. 

 Woodward and P. Fischer's " Manuel de Conchyliologie," 

 1887. The six molluscan regions correspond almost exactly 

 with those of Wallace^ with this exception, that the Pata- 

 gonian or Chilian sub-region is elevated to the rank of a 

 seventh region. 



In dealing with the distribution oi flying creatures, the 

 author rightly draws attention to the circumstance that 

 the recent volcanic outbursts of Krakatab might have killed 

 all the terrestrial inhabitants with the exception of such 

 animals as could fly to neighbouring islands. Therein 

 lies, according to M. Trouessart, the explanation why the 

 Polynesian islands are inhabited by bats and birds only, 

 some of which are peculiar island forms. But these he 

 considers to be the last survivals of a Polynesian fauna, of 

 which we have now only dispersed members. This is one 

 of those perplexing ideas which, although arrived at by a 

 perfectly logical process of thinking, are nevertheless 

 without any real justification. 



For the distribution of birds Dr. Reichenow's six zones 

 have been adopted ; these zones are widely different from 

 the now time-honoured six regions. 



Arctic Zone 

 Oriental Zone Occidental Zone 



Oriental Temperate Region Occidental Temperate Region 



1.1 I 



Ethiopian Region Malayan Region South American Region 



Madagascar Zone Australian Zone 

 Antarctic Zone. 



The Oriental and Occidental zones are, of course, 

 nothing but the Palaeo- and Neogsea ; the word zone 

 should not be applied to eastern and western hemispheres, 

 but rather to horizontal belts. Dr. Reichenow lays stress 

 upon the idea that the annual migration of European 

 and of Asiatic birds shows their connection with the 

 Ethiopian and Malayan regions ; hence their combination 

 into one zone, together with what has been called hitherto 

 the Palasarctic region. Madagascar has been elevated 

 to separate rank, and so have the Arctic and Antarctic 

 NO. 1078, VOL. 42] 



zones, so that on the whole the old arrangement (based 

 by Dr. Sclater chiefly upon birds) has been completely 

 altered. Birds are far less cosmopolitan than one might 

 suppose, judging only by the strength of their wings. 



The distribution of Lepidoptet-a is rather surprising, 

 because the applied schematic representation shows that 

 there are only three great regions. The New World, from 

 Canada to Cape Horn, stands alone ; Africa forms only 

 a sub-region of the large Holarctic region, which includes- 

 Canada ; while Australia forms a sub-region of the Indian 

 region, which again gradually merges in the eastern half 

 of the Holarctic. These results, however, are based upon 

 the somewhat antiquated conclusions drawn by Koch and 

 Staudinger in 1850. 



Holarctic Region 

 I I 



American Region African Indian 



Sub-region Region 

 I 

 Australian Sub- region. 



According to the Spanish naturalist, J. Bolivar, the dis- 

 tribution of the Orthoptera, which, being possessed of 

 great power of flight, are given to long migrations, agrees 

 rather with that of a part of the Coleoptera. 



Pp. 280 and 281 contain a map of the world, on Mer- 

 cator's projection, upon which the principal ocean cur- 

 rents are indicated, and by conventional signs the distri- 

 bution of seals, sea-lions, penguins, and auks. The Sphen- 

 iscidse have been carried along the west coast of South 

 America as far north as the Galapagos Islands by the 

 cold Humboldt's current, a circumstance which, by the 

 way, was first pointed out by the late Dr. Watson in 

 his Challenger Report on the Spheniscidse. The Pinni- 

 pede genus Macrorhinus follows strange lines across the 

 Pacific Ocean, apparently in conformity with existing 

 currents, but the conclusions as to the original home of 

 these sea-elephants seem somewhat far-fetched. The 

 seal Pelagius monachus, until recently considered a chiefly 

 Mediterranean species, is known to occur at the Canaries 

 and at Madeira. Another closely allied species, P. tropi- 

 calis, Gill, has been discovered at certain lonely islands off 

 Yucatan. But is it probable that this species owes its origin 

 to a small group of the Mediterranean species, which has 

 been carried across the Atlantic, past the numerous Antillearb 

 islands, almost to the mainland of Central America, there 

 to be transformed into a new species .? Is it not more 

 likely that the occurrence of Mediterranean seals in 

 the Atlantic is due to a formerly wider extra- Mediter- 

 ranean distribution, especially since remnants of such 

 seals have been found recently in the Furfoz caves near 

 Setubal ? 



The eleventh chapter deals with the faunas of deep seas,, 

 high mountains, coast zones, lacustrine and subterraneous 

 regions. 



The twelfth, the last chapter, gives a very short account 

 of the distribution of animals in time. Hardly any types 

 of fossil animals are known to have existed in all regions 

 of the globe. The largest animals enjoyed the most 

 restricted range, both in space and in time. The small 

 size and the early occurrence of mollusks and insects 

 explain their now almost cosmopolitan distribution, 

 while the greater abundance of Tertiary mammals, with 

 their subsequent local extermination, gives the clue to- 



