based on the Principle of Cephalization, 89 



as represented in the Carnivores, the deficiency of teeth would be 

 an example of dccephalization by the elliptic method ; for such a 

 deficiency under the higher type of the Carnivores would be evi- 

 dence of abnormal weakness. 



The same principle is exemplified in Carnivores ; for the size 

 and number of the molar teeth are less the larger the canines. 

 The Machaerodus, with its huge tusks and but three molars to 

 either side of a jaw, is a remarkable example. Again, in the 

 Elephant, two incisors are developed into the great tusks of the 

 upper jaw at the expense of the other incisors and canines ; and 

 jaws that look as if bearing profoundly the mark of degradation 

 or dccephalization, are hence compatible with high cejphaUzation 

 under the Herbivore-type. 



It is not to be inferred that the enlargement of one part of an organ 

 at the expense of the others, is necessarily an indication of general 

 elevation of grade. Even in the case of the foot of the Plorse, the 

 elevation implied is elevation only under the Horse-type or among 

 Solidungulates, and not elevation above all other Herbivores. 



These examples are sufficient to illustrate the contrast between 

 the elliptic method of cephalization and of dccephalization ; and 

 also the fact, that a case of the former in one relation may be one 

 of the latter in a higher, that is, if referred to a higher group as 

 the standard type. The cases that would come under the elliptic 

 method of cephalizatiGn (as that of the Crab) have been already 

 referred to by the writer to the concentrative, they being a result of 

 concentration in the life-system. 



(3.) That simplicity of structure which is opposed to the special- 

 ized or differentiated condition of superiority of type. — It is evident 

 that the examples of elliptic dccephalization, taking this term in its 

 most comprehensive sense, may include the various simplifications 

 which mark unspecialised structures of inferior types. Yet we 

 propose to restrict the term to those examples of deficiencies which 

 are obviously connected with degradational or hypotypic conditions 

 under any type. 



Viewed on the ascending grade, this method is the completive. 



10. Phytozoic. — Exhibited in a departure from the Animal-type 

 through a participation in structural features of the Plant- type, 

 that is, through a plant-like arrangement of the organs. The 

 cases are — 



a. A radiate arrangement of external organs ; as in the Bryo- 

 zoans and inferior Tunicates. 



b. A radiate arrangement of internal as well as external organs; 

 as in Radiates. 



c. Perfect, or nearly perfect, symmetry in the radiation, instead 

 of eccentric or irregular forms. Perfect symmetry is most gene- 

 ral where the number of rays is based on the numbers 4 or 6 



NEW SERIES VOL. XIX. NO. I. JANUARY 1864. M 



