dJ' 



NATURE 



{Feb, 24, 1876 



mules, or the number present in particular cases, but it 

 appears to me interesting to consider how far the theory 

 will hold good when examined from this more physical 

 point of view. 



For the sake of argument, I assume that gemmules on 

 an average contain one million structural molecules of 

 albumen and molecularly combined water. Variations in 

 number, composition, and arrangement would then admit 

 of an almost infinite variety of characters. On this sup- 

 position it would require a thousand gemmules to be 

 massed together into a sphere, in order to form a speck 

 just distinctly visible with our highest and best magnify- 

 ing powers. By calculation I find that a single mamma- 

 lian spermatozoa might contain so many of such gem- 

 mules, that, if one were lost, destroyed, or fully developed 

 in each second, they would not be completely exhausted 

 until after the period of one month. Hence, since pro- 

 bably a number are concerned in producing perfect fertili- 

 sation, we can readily understand why the influence of 

 the male parent may be very marked, even after having 

 been, as regards particular characters, apparently dormant 

 for many years. 



In a similar manner I calculate that the germinal 

 vesicle of a mammalian ovum might contain enough 

 gemmules for one to be destroyed, lost, or fully developed 

 in each second, and yet the entire number not be ex- 

 hausted until after a period of seventeen years, and the 

 entire ovum might contain enough to last at the same rate 

 for no less than 5,600 years. 



These calculations are made on the supposition that the 

 entire mass is composed of gemmules. Of this there is 

 little probability ; but still, even if a considerable portion 

 of the ovum consists of completely formed material and 

 of mere nutritive matter, it might yet contain a sufficient 

 number of gemmules to explain all the facts contemplated 

 by the theory of pangenesis. The presence of any con- 

 siderable amount of such passive matter in spermatozoa 

 would, however, be a serious difficulty in the way of the 

 theory, unless indeed very many spermatozoa are in- 

 variably concerned in producing fertilisation. 



Taking everything into consideration, it does not 

 appear to me that any serious objection can be raised 

 against pangenesis when examined from a purely physical 

 point of view, as far as relates to the inheritance of a very 

 complex variety of characters by the first generation, 

 though there would have been may serious difficulties to 

 contend with, if the ultimate atoms of matter had been 

 very much larger than is indicated by the properties of 

 gases. 



When we come to apply similar reasonings to the 

 second or following generations, we are compelled, along 

 with Darwin, to conclude that gemmules have the power 

 of producing other gemmules more or less closely re- 

 sembling themselves, and of being collected together in 

 the sexual elements, since otherwise the number that 

 could be transmitted in a dormant state for several genC' 

 rations would be far too small to meet the requirements 

 of the case. 



Conclusion. 



In my remarks I have made no endeavour to conceal 

 our present ignorance of many very important questions 

 connected with my subject. Want of the requisite data 

 necessarily imparts a speculative character to many of 

 my conclusions ; but perhaps there is no more fruitful 

 source of knowledge than to see and feel how little is 

 accurately known, and how much remains to be learned. 



THE TUFTED DEER OF CHINA 



A MONG the many most valuable additions which Mr. 

 -^*- R. Swinhoe has made to our knowledge of Chinese 

 zoology, there are none more important than his disco- 

 veries in the deer-tribe. The Water Deer of Shanghai 

 {Hydropotes ittermis), first described in 1870, is one of 



the most interesting of these. It is of small size, without 

 horns of any kind, and with long canine teeth present in 

 the males only. In outward appearance it in these re- 

 spects closely resembles the Musk Deer. Its colour is 

 liuht chestnut, and the hairy coat is harsh. It is called 

 the Ke and the Chang by the Chinese. Sir Victor Brooke 

 has demonstrated that its skull differs in important points 

 from that of Mosckus. 



Still more recently, in 1874, Mr, Swinhoe has described 

 another small deer from the mountains near Ningpo, of 

 much the same size as Hydropotes j it also resembles that 

 genus in being hornless and possessing large canine tusks 

 in the males. Mr, Swinhoe, in the " Proceedings " of the 

 Zoological Society (1874, p. 452), writes as follows : — 

 " My friend and correspondent, Mr. A. Michie, wrote me 

 a letter dated Shanghai, December 19, 1873, ^s follows : — 

 ' I send another note to overtake the mail, to tell you I 

 have just found a new deer from the Ningpo country. It 

 is a dark iron-grey or pepper-and-salt colour, like some 

 Scotch terriers, with white tips to its ears, square-built (that 

 is, straight back and pointed hip), with very short tail. On 

 its forehead is a thick black mane, like the bristles of a 

 boar. ... It has the lachrymal sinus, but not so large as 

 the Muntjac ; in size the beast about equals the Muntjac' " 

 An excellent figure accompanies this description. It was 

 drawn from a skin sent by Mr. Michie to Mr. Swinhoe, 

 who has named the animal LopJwtragus michiatiits. 



A living example of this species, the first ever brought 

 to this country, has just reached the Zoological Gardens 

 in Regent's Park. From this male specimen it can be 

 seen that the drawing above referred to, made from the 

 flat skin, excellently represents the figure of the animal, 

 and is truthful in that it shows the canine teeth and the 

 absence of horns. In the living specimen there is a pair 

 of hair-covered tuberosities on the frontal regions, at the 

 postero-lateral angles of the hairy head-tuft, but, as in 

 the Giraffes, these have no horns upon them. Comparing 

 this condition with that of Elaphodus cephalopJms, also 

 from China, described by M. A. Milne-Edwards, the inti- 

 mate relation oi Lophot7'agiis to the Muntjacs {Ccfvulus) is 

 evident ; the series of gradual antler-reduction being in 

 the following order : — Cervulus, Elaphodus, Lophotragits. 

 Whether Hydropotes, or Moschics, or both are extremes of 

 this series, remains to be proved ; and it must be men^ 

 tioned that it is not perfectly certain, though highly 

 probable, that the above-described individual specimen 

 of Lophotragits exhibits its highest degree of antler- 

 development. 



NOTES 



Some weeks since it was stated that the collection of fishes 

 made by Mr. Francis Day, Inspector-General of Indian FisherieSj 

 would be deposited in the New Indian Museum at South Ken- 

 sington, It was offered to and accepted- by the Secretary of 

 State for India, but it was subsequently considered that neither 

 the expense of bottles in which to exhibit them, nor of spirit for 

 their preservation, could be rightly debited to the resources of 

 India, Mr. Wood, the well-known artist, very liberally pro- 

 posed, in exchange for the type collection, numbering about 

 1,200 species, to increase Mr. Day's plates in his work, the 

 "Fishes of India," from 160 to 190, or to 1,140 figures. The 

 Director of the Indian Museum in Calcutta hearing of this 

 arrangement, proposed to the trustees that he should secure it 

 at once on these terms, and we understand that he has been 

 instructed to do so. It will doubtless render the Museum in 

 Calcutta the most complete in Indian fishes in the world ; but 

 whether this collection finding a place in the British Museum 

 might not have proved more beneficial to science we leave for 

 the decision of our readers. 



Mr. Willett has just issued a report on the Sub-Wealden 

 boring, stating that the bore-hole has been widened and lined to 



