
PROCEEDINGS OF SCIENTIFIC SOCIETIES. 4441 
T retreat during the summer months it is unexcelled in the purity and 
oolness of its Quir got the clearness eh its flowing streams, and its 
et. extended views 
Prof. E. D. Cops, in Es paper “On the Larval Characters of the Uro- 
dela," stated: 1st, That it is shown that one portion of the primary — 
groups is inexactly parallel to larvel stages of the other portion. 2d, 
certai 
other genera by but two characters. 3d, That others lack but one char- 
acter; and 4th, That others present an exact paralleli 
He had reason to think from the development d EUM and 
experiments on salamander and frog larve, that the process of growth 
or assumption of generic characters may be much retarded or acceler- 
ated. Such a process would produce the cases of exact parallelism; and 
if the retardation in the character should continue, would necessarily 
Soon result in inexact parallelism in that respect, thus producing a com- 
plete metamorphosis of the genus. The reverse of this process is ac- 
celeration, and expresses the mode of progress of a type to its highest 
development in time history, while the retardation is the mode of its deg- 
dation. 
T remarked that Prof, Cope’s views were, so far as the law 
Ceph Among these animals the shells of the species displaye 
the action of this law from a previous publication in th 
had been distinctly stated. But farther than this that its action was also 
as forcibly displayed in the species itself as in the genus. 
Mr. A. Hyarr read a paper *On the Homologies and General Structu- 
ral Relations of the Pol yzoa." The Embryology of the Hypocrepian Poly- 
zoa show that Loxosoma is the lowest of all in the na nie toget ther 
with Pedicellina form the lowest suborder of the group. progress 
9f the whole order of Polyzoa is from this permanently VEI form 
Pirongh intermediate stages to Cristatella, in which, when the polypide is 
inserted, even the stomach is carried up beyond the orifice of the ce 
Thus the progress of structure is from an animal i 
are crowded into the anterior end, into the ccencecial system, and to one 
in which the ccnccial or re productive, evaginatory or gastric, and the 
lophoric or neural systems are all distinct when the animal is exserted. 
T 



era. NATURALIST, VOL. III. 


