252 



INDIAN CYPRINID^. 



pass through a succession of species connected together by direct relations, and 

 after arriving at an opposite point f OpsariusJ at which the forms, habits, and 



other in nature, Cuvier and Valenciennes observe, " lie alone could build up such a pretension who 

 would attempt to place animated nature on a single line, a project which we have long since re- 

 nounced as one of the most false that could be entertained in natural history." — Historie Naturelle 

 des Poissons. 



On the same subject, another authority observes — " The day is now happily gone past when 

 zoologists thought that the infinite variety of animals which inhabit this globe owed their origin to 

 the unsuccessful efforts of nature before she could attain the human structure as her term of 

 perfection." — Macleay — Lin. Transac. 



" 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." — Swainson'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 simplest form is circular, but there is no 

 objection to the progression of affinities being square or oval, provided they can be proved to be so; it 

 is less the form tlian 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 Affinitatmn 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. Lin. Transac. vol. 14, p. 49. 

 M. Lamark detected the existence of a double series which setting out in opposite directions from a given 

 point met together at another. Unacquainted with the result to which Lamark had been led. Prof. 

 Fischer in 1808, perceived a tendency in the series of affinities to form acii'cle ; but these obscure inti- 

 mations were first established by analyses in the Horse Entomologicse of Mr. Macleay published in 

 1819. Since then Mr. Vigors submitted a general analysis of the whole class of birds to theLinnsean 

 Society, 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 publica- 

 tion recorded in the Linnsean Transactions, in which the same principles were applied by Mr. Macleay 

 to the whole animal kingdom. The birds of New Holland were subsequently examined by Blessrs. 



