194 Mr. J. M'Clelland onhulian Cyprinidae. 



from a suborbitar sinus analogous to the suborbitar sinus in 

 Antelopes, the use of which in them is conjectural. The horn, 

 which is concealed in this sinus in the Loaches, appears to be 

 equivalent to the suborbitar chain in the Perch, and to the 

 corresponding plates in the ordinary Cyprinidce ; it is some- 

 what flattened or palmated, as in many of the Deer tribe, 

 ending in a sharp point which is directed forward : on the an- 

 terior margin, and near the base of the horn, a strong antler 

 is given off; this is also veiy sharp, and turned forward like 

 the point of the horn itself. 



49. I have shown that Cyprinidoi is a natural group, that 

 it is circular^ in its affinities; that, for instance, in setting out 



* " They might as well be called oval or square." " Why not linear? " 

 The researches of zoologists during the last twenty years ha%'e fortunately 

 left me nothing original to say in reply to this criticism, which jjerhajis de- 

 serves notice as coming from a member of the committee of papers, Mr. 



C . Speaking of describing natural objects in the order in which they 



succeed each other in nature, Cuvier and Valenciennes observe, " He alone 

 could build up such a pretension who would attempt to place animated na- 

 ture on a single line, a project which we have long since renounced as one 

 of the most false that could be entertained in natural history." — Histoire 

 Naturelle des Poissons. 



On the same svibject another authority observes : — " The day is now hap- 

 pily gone past when zoologists thought that the infinite variety of animals 

 which inhabit this globe owed their origin to the unsuccessful efforts of na- 

 ture before she could attain the human structure as her term of perfection." 

 — MacLcay, Linn. Tr ansae. 



" As to the rule of natural progression, is it linear ? The idea of a simple 

 scale in nature had long been discussed and finally abandoned." — Swain- 

 son's Discourse on the Study of Natural History. 



As all natural objects have three relations of affinity, it is clear the chain 

 that connects them cannot be straight, and not being straight, the next sim- 

 plest form is circular; but there is no objection to the progression of affini- 

 ties being square or oval, provided they can be proved to be so ; it is less 

 the form than the circumstance of the opposite extremes of a natural series 

 meeting that is insisted on. 



Some notion of circular affinities appears to have existed from an early 

 date. Hermann, in his ' Tabula Affinitatum Animalium,' published in 1783, 

 as Mr. MacLeay points out, refers to an earlier writer, who like himself 

 seems to have had a glimpse of the same truth (' Linn. Transac.', vol. xiv. 

 p. 49). M. Lamarck detected the existence of a double series, which setting 

 out in opposite directions from a given point, met together in another. Un- 

 acquainted with the result to which Lamarck had been led, Prof. Fischer, in 

 1808, perceived a tendency in the series of affinities to form a circle; but 

 these obscure intimations were first established by analyses in the ' Horae 

 Entomologicae ' of Mr. MacLeay, published in 1819. Since then Mr. Vigors 

 submitted a general analysis of tlie whole class of birds to the Linnjean So- 

 ciety, in all the groups of which he found the affinities to confirm what had 

 been observed by Mr. MacLeay during his examination of insects, as well as 

 the views contained in a subsequent publication recorded in the ' Linniean 

 Transactions,' in which the sanm principles were applied by Mr. MacLeaj' to 

 the whole animal kingdom. The birds of New Ijolland were subsequently 

 examined by Messrs. Vigors and Horsfield with the same result (vide ' Lin- 



