114 F. Stoliezka — On the Passalidce. [Mat, 



the sacral region should be the most developed part of the body in the Mol- 

 lusca. 



The general plan exhibited in the above table is, however, followed by 

 Dr. Kaup through all the five sub-kingdoms. Thus, he places — and I think 

 rightly — the PsiUacidce, as the most highly organised of birds, in the first fa- 

 mily of the five tribes into which the birds are divided. On the same principle 

 the Brevvpermes with the Dinomidce form the centre of the third tribe, and the 

 OaUinacece, which are the most stupid birds, take the lowest position. Among 

 Reptilians the Chameleontidce are the highest, and the Dinosaurii the 

 largest ; the former belonging to the first, the latter to the third tribe. 



The above table is thus applied to every group, and is carried into the 

 greatest detail in the Passalidce. The largest known form, Proculus Gori/i, is 

 considered as the centre of the family, which is separated into Aulacocyclince 

 Eriocnemina, Proculmce, Neleince, Passalince. Dr. Kaup complains, that 

 naturalists very often mistake analogies for affinities. Nature, he says, does 

 not like affinities, but dissimilarities, and consequently in a natural arrange- 

 ment not the species following each other, but always the next following is 

 affined to the preceding. Each genus of the Passalidce is thus divided into 

 five species, of which the first is small and most convex, the second smallest 

 and most depressed, the third the largest, the fourth smaller and the fifth 

 the next largest. This system is carried out in a really most wonderful 

 way, and the exceptions to it are apparently very few. Only in one instance, 

 in the genus Basiliauus, has the author described seven species, but these 

 form two different groups, which are, however, by Kaup himself regarded as 

 belonging to the same genus. In Leptaulax one species is added, but 

 another which Dr. Kaup adopts, is believed to be merely a synonym. 

 This new law of development, or whatever it may be called, is believed by 

 its originator to be the greatest discovery which systematic zoology has 

 made. We must leave it to time and research, which will no doubt tell us 

 the real value of this practical philosophic idea. In the present instance 

 the author thought it only desirable to bring the rudiments of the system, 

 as stated by Dr. Kaup, before the members of the Society, and expressed a 

 hope that somebody would give a little thought to it. 



Speaking of recent suggestions, Dr. Stoliezka thought he might allude 

 to one affecting the system of nomenclature in Zoology. All these 

 suggestions, whether they become generally acknowledged or not, shew the 

 direction in which the working zoological minds of men are at present 

 occupied. 



Professor Halting in Utrecht has recently drawn the attention of 

 zoologists to the unsatisfactory conditions under which zoological nomencla- 

 ture labours. The number of names is becoming so varied and so alarmingly 

 large, that no human mind can remember these heterogeneous appellations. 



