134 EMINENT NATURALISTS. 



animals which have not red blood — more than half of 

 the animal kingdom. Cuvier's first researches were on 

 this class of animals, which in 1795 he divided into 

 the classes of his invertebrate series. 



His very first observations in 1792 were on the 

 anatomy of the common patella, certain dipterions 

 insects, and crustaceans, in the " Journal d'Histoire 

 Naturelle." In the same year he studied the structure 

 of the mollusca, divided them into orders, and com- 

 menced a series of observations which resulted in his 

 memoir on the history and anatomy of molluscs, 

 published in 1817. 



Comparative anatomy was the basis of Cuvier's 

 zoology, and we find memoirs on this subject from 1795 

 to 1831. The " Lecons d'Anatomie Comparee " was 

 but the preface of a more extended work, the plan 

 of which he had already completed when death over- 

 took him. Such as it is — a monument of vast labour' — 

 it has furnished materials for the development of this 

 science, and has from its own stores enabled critics to 

 point out unavoidable deficiencies. From a heap of dry, 

 unconnected facts concerning the structure of animals, 

 he obtained the general laws of organization, the limit 

 of variation in each organ, the marked influence of 

 some upon the general system, the subordination of 

 many, and the co-existence or incompatibility of others. 

 Among the prominent points are : the development of 

 the teeth, the structure of the larynx of birds, of the 

 nasal fossae and organs of hearing in cetaceans, and 

 of the respiratory organs in the perennibranchiate 

 amphibia ; the comparison of the brain in the verte- 



