REMARKS ON THE PRI3IARY DIVISIONS. 13 



vertebrate circle. Without this there could be no 

 mutual relationship, no harmony of parts ; and all that 

 has been written on the analogies of the animal creation 

 would fall to the ground. Either the natural arrange- 

 ment of the Annulosa coincides with those principles 

 which regulate the variation of the Vertehrata and all 

 other animals, or we must adopt the preposterous sup- 

 position that they have been formed upon a totally 

 different plan. Now this idea, improbable in itself, is 

 falsified by the comparison we have just laid before the 

 reader. It therefore follows, that no arrangement of 

 the Annulosa can, by any possibility, be a natural one, 

 unless it developes analogies to the Vertebrata equally 

 strong with those we have just stated. We are not 

 now speaking of the details, for an arrangement may be 

 substantially true in its outlines, — it may even be based 

 on the foundation of truth, and yet may be defective 

 or erroneous in some parts of its superstructure. This, 

 however, is an after-consideration. The primary groups, 

 still less the general principles, will never be affected 

 by such inaccuracies ; and in the meantime we get what 

 is of the highest importance to the philosophic zoologist 

 — a definite notion on the value of those groups employed 

 in the comparison, groups which have been acknow- 

 ledged by all writers, but upon whose value not any two 

 have hitherto agreed. The Crustacea, for instance, were 

 considered by the fathers of entomology as an order 

 equivalent in value to the Coleoptera. But Cuvier, at- 

 taching an undue importance, as he frequently did, to 

 these animals, breathing by a different set of organs to 

 winged insects, made them into a class. This innova- 

 tion Avas soon followed up by another, and Lamarck on 

 similar grounds elevated the spiders to the same rank. 

 This mistaken principle, once sanctioned by such names, 

 induced almost every succeeding author to make fresh 

 classes and orders ; until the apterous insects, one of 

 the most natural in the whole animal kingdom, have at 

 length been thrown unto the greatest confusion : all the 



