LINN^AN SYSTEM. 141 



or quadrupeds; 2. Aves, or birds; 3. Amphibia, or 

 reptiles ; 4. Pisces, or fish ; 5. Insecta, or insects ; and 

 6. Vermes, or worms. These he distinguishes in the 

 following manner ; — 



Cuv. M'Leay. 



I. r 



Heart with two auricles) Viviparous. Mammalia. lb. lb. 



and two ventricles j bluod J Oviparous. Birds. lb. lb. 



warm, red . . (. 

 Heart with o'!e auricle and^^ungs voluntary. Amphibia. lb. [ \^^^l^^_ 



one ventricle ; blood cold, i External gills. Fishes. lb. lb. 



red - - - C 



"I- rrtenn^"'"'^"»'='«- I"- 



Heart with one auricle and^ Furnished with i Mcllusca. 



no ventncle i sanies cold, ] antennie with f Worms. Acr.ta. • 



t white - ■ • L tentacula. J Kadiata, ; 



(193.) Considering the period when this scheme was 

 drawn up, we must allow it the credit of being much 

 more definite and practically useful than any of those 

 which it supplanted : we allude more especially to the 

 two latter divisions, in reference to the object which our 

 author had in view, namely, the ready determination of 

 the name of a species. The whole is confessedly an 

 artificial system ; and the author has obviously made the 

 class Vermes a general receptacle for all those invertebrat- 

 ed animals which could not be classed with any other 

 class. When, therefore, we express surprise that a genius 

 like Linnaeus could have brought together animals so 

 totally different in their nervous system, their internal 

 anatomy, and their external organisation, we must re- 

 member the remoteness of the period at which he wrote, 

 the state of knowledge at the time, and the mistakes, 

 equally glaring, which from the same causes his predeces- 

 sors^even Aristotle himself, have equally committed. Be- 

 sides, it must be confessed that the Linnsean Vermes, not- 

 withstanding our increased knowledge of their true nature, 

 have so many external points of general similitude, that 

 we can feel no surprise at the whole being considered as 

 one group: nor is it, in fact, at all improbable that they 

 actually are so. For if, as there is good reason to sup- 

 pose, reasoning analogically, the modern classes o{ Acrita, 

 Mollusca, and Radiata form a circle of their own, then 



