based on the principle of Cephalization.—Insects. 11 
circumferential diffusion, and may be designated apocentric; in the 
other, the ascending, it is cephalic concentration or epicentric—the sys- 
temic centre here referred to corresponding in position to the cephalic 
nervous mass or brain (p. 322). 
The degrees of concentration do not generally shade indefinitely into 
one another. There is a range of variations under a given ype or spe- 
cific condition of the systemic force; and then a drop-down or saltus to 
_ IL In a superior group, (A) compactness, regularity and per- 
fection of structure, with normal proportions and narrow limits 
of variation. 
the latter), or a lengthening or attenuation of limbs (long-amplifi- 
cate), or in a general enlargement (large-amplificate, gross-ampli- 
cate); (D) a multiplicate condition, or an indefinite multiplica- 
‘tion of segments or members, as in Myriapods and Worms, and 
Opposed to a limitate condition like that of Insects, Spiders, and 
Crustaceans; (E) an analyzed or elementalized condition, being a 
mor ion i 
more or less completely defunctionated condition of any organs or 
members. (P. 324. 7 
V. Sup., (A) a terrestrial mode of life in all stages.—Inf,, (B) 
an aquatic mode of life, (a) in the adult stage, but not connected 
with aquatic respiration ; (4) in the larval stage only; (¢) in 
all stages, with aquatic respiration throughout each. A terres- 
trial mode of life in all stages may be distinguished as perlerres- 
‘y and an aquatic mode of. life in all stages with aquatic 
f 
