,i8 



NATURE 



[Sei'TEmber 9, 19C9 



the whales will disappear the whale-lice and the whole of 

 the very interesting parasitic fauna which inhabit their 

 vast interiors. 



The disappearance of the large game from enormous 

 tracts of country in Africa is too well known to delay us. 

 The elephant, except where preserved in the Litzikama 

 Forest, near Mossel Bay, and in the Addo Bush, near Port 

 Elizabeth, is exterminated south of the Limpopo. The 

 price of ivory, again, is a measure of the nearness of its 

 extinction, the best pieces, which are used for billiard 

 iKills, have risen in price from '55/. a cwt. in 1882 to an 

 average of looi. a cwt. in 190S. The common and the 

 brindled gnu (Connodioeies taitrinus) are fated to follow 

 the extinct quagga. The blesbok {Damaliscus albifrons), 

 formerly found in thousands in Cape Colony, the Trans- 

 vaal, and Bechuanaland, is now very rare, and seems 

 doomed. The giraffe has long been driven out from South 

 Africa, though it still roams over large tracts of country 

 in East and Central Africa. 



Perhaps the most striking case of the disappearance of 

 a mammalian fauna is that presented in Western Australia. 

 Here manv districts are now said to be entirely devoid 

 of indigenous mammals, and this depletion is in the main 

 an affair of only the last thirty years, and many of the 

 local extinct forms are still remembered by the older natives 

 and colonists. Mr. Shortridge, a collector who has worked 

 for some years in .South-west and Western Australia, writes 

 in a letter : " The entire disappearance of so many species 

 over such large tracts of country is generally considered 

 to be due to some epidemic perhaps brought into the land 

 by introduced animals. It is to be noted that they have 

 died out chiefly in the dry regions, where, except for the 

 introduction of' sheep, there has been very little alteration 

 in the natural conditions. Rabbits, although already very 

 numerous in the Centre and South-east, have not as yet 

 found their way to the North-west." Amongst the 

 mammals which have almost, if not quite, disappeared 

 from West Australia are the banded wallaby (Lagoslrophus 

 fasciatus), the hare wallaby (Lagochestcs hhstitus), the 

 rat-kangaroos (Potorous gil'bcrli and P. platyops). The 

 indigenous rats and mice of .'\ustralia are disappearing 

 even faster than the marsupials, and it seems probable 

 that many will not be heard of again. 



A very few years ago the ship employed by the company 

 which is exploiting the phosphates of Christmas Island 

 introduced the brown rat {M. decumaims) there. Within 

 a short time the two indigenous rats first collected by Mr. 

 C. W. Andrews, of the British Museum, named Mits mac- 

 leari and Miis novitatis, were wiped out of existence. The 

 same animal having been introduced in North .America is 

 gradually spreading, and as it spreads the native fauna of 

 Muridae is slowly vanishing. 



To adorn our ladies' heads some of the most beautiful 

 of birds are being systematically exterminated. In the 

 London market alone were sold last year some 50.0°° 

 sooty terns (,Sterna fiiliginosa, S. anaestheta, and ,S. 

 honata), 20,000 specimens of the crowned pigeon (Goura) 

 from New Guinea, their sole habitat, immense numbers 

 of " osprey " feathers, egret and heron, and more than 

 i;o,ooo birds of paradise, or more than double the number 

 of the year before. 



I have no time to continue this melancholy record, but 

 it could be prolonged almost indefinitely. 



When wo reflect how greatly we treasure every scrap 

 of knowledge we can glean about such recently extinct 

 animals as the Rhytina — Steller's sea-cow — the dodo, the 

 great auk, we must see that if it be impossible to check 

 the gradual disappearance of those animals doomed to 

 extinction, we should at least monograph them and take 

 every care that what can be permanently kept of their 

 structure should be kept. In respect to the recording of 

 the habits and physical features of a disappearing race, 

 the anthropologists are setting an example which the zoo- 

 logists would do well to follow. 



We are living with a disappearing fauna around us, and 

 numerous as the museums of the world are, and skilled 

 and painstaking as the curators of these museums are. 

 they are both wholly inadequate to deal with the material 

 at hand. Some dozen years ago Dr. Giinther made a very 

 careful estimate of the number of species of animals which 



NO. 2080, VOL. 81] 



were known in the years 1830 and 1881. I summarise his 

 table :— 



Number of Species known in the years 1S30 and 1S81. 



73,588 311.653 



Taking an average year between 1881 and the present 

 date, but rather nearer the latter, because each year the 

 number of newly described species becomes larger. Dr. 

 Sharp tells me that, according to the zoological record, 

 12,449 — 'et us call it 12,450 — new species were described 

 in the year 1897. 



Number of new Species described in the year 1897. 

 Mammalia 285 



'05 



140 

 148 



1.077 



7 



6 



239 



659 



27s 



S.364 



491 



294 



Aves 



Reptilia and Balrachia 



Pisces 



MoUusca 



Brachiopoda 



Bryozoa 



Crustacea 



Arachnida 



Myriapoda 



Insecta 



Echinodermata ... 



Vermes 



Coelenterata 

 Porifera 

 Protozoa ... 



164 



95 

 100 



12,449 

 This number, however, includes fossils which I do not 

 think were igcluded by Dr. Giinther. We might deduct 

 450 for them if we wisli to confine our attention to living 

 animals. This leaves us 12,000. If we multiply this by 

 27, the number of years which have elapsed since Dr. 

 Giinther made his estimate, we find a total of 324,000. 

 This number is possibly too large, as it makes no allow- 

 ance for synonyms ; still, it is a rough indication that 

 since 18S1 the number of described species has been 

 doubled. Isolated groups, such as the mammals, treated 

 in the same way, give us fairly similar results, so that 

 now we may, I think, say that there are more than 

 600,000 described species of living animals. 



It thus appears that during the fifty-one years in the 

 middle of the last century the number of known species 

 grew by some 238,000, giving an average increase of a 

 little less than 5000 per annum. At the present day there are 

 far more workers in the field than there were thirty years 

 ago, museums have multiplied, and there are many more 

 zoologists, and it is now estimated that the number of 

 species annually described and named amounts to some 

 12,000. 



The number, large as it seems, is, however, but small 

 in comparison with the number of species collected and 

 deposited in museums where no one has time to work them 

 out. It is still smaller in comparison with the vast 

 numbers of species as yet uncaptured. Dr. Sharp, in 

 1895, calculated that there were a quarter of a million 

 known and described insects. This was an increase of 

 30,000 over Giinther's figures of fifteen years before, but 

 he states that in his opinion this quarter of a million is 

 but one-tenth of those which exist. 



