based on the Principle of Ceplialization. 91 



development and low rank ; and the following is the explanation 

 of it : — 



When an animal has reached the condition required for locomo- 

 tion and for the care of itself, it has already the essential faculties 

 of an adult; and although these faculties of locomotion and self- 

 feeding are of comparatively low grade, the animal possessing 

 them is approximately mature in its cephalic forces, and after- 

 wards rises but little with growth. Prematurity hence involves 

 inferiority. The pupa-state of an Insect is a means of higher de- 

 velopment the more perfect its inactivity. For this complete rest 

 allows all the forces of the individual to be concentrated on the 

 internal processes, and favours, therefore, that cephalic growth 

 which makes a special demand on these forces ; while in an active 

 pupa (or rather the larve that passes through no pupa-state), 

 activity, whether that of locomotion, or of digestion, constantly 

 exhausts force ; and only the balance, not thus run away with, 

 goes towards the maturing process. With such an open outlet of 

 force, the animal may mature physically, that is, grow and perfect 

 its outer structure; but cephalically, or, in all those points of 

 structure, as well as psychical powers, that are connected with 

 superior cephalic development, it makes little advance. 



Hence (a), those insects whose larves are essentially like the 

 adults, and undergo no metamorphosis, are inferior in type, — as 

 generally so recognised. 



Again (6), those Insects (as most Hymenopterous) whose larves 

 are footless grubs are superior in type to those (as the Lepidop- 

 terous) whose larves are most highly developed and active. 



Viewed on the ascending grade, this method is the perma' 

 turative. 



13. Gemmative. — Exhibited in multiplication by buds. Bud- 

 ding may produce — 



a. Perfect individuals, capable of egg- production. 



6. Individuals capable only of budding, and giving origin to 

 a perfect egg-producing individual, as the last of a series of 

 buddings. 



c. Caducous, or persistent buds ; the latter leading to compound 

 forms, either branching, lamellar, or massive. 



This power of reproduction by buds occurs in many Worms, 

 both superior and inferior ; in Bryozoan and many Ascidian 

 Mollusks ; in Polyps and many other Radiates. The production 

 of persistent buds is the lowest grade, and is common in the bud- 

 ding Mollusks and Radiates, but not the Articulates. Among 

 budding Articulates, case b appears to be of lower grade than 

 case a. 



This method is allied to the multiplicative, p. 85. It is also 

 phytozoic (p. 89), or a plant-like feature in animal life. 



