lachdruck verboten. 
/bersetzungsrecht vorbehalten, 
On the habits and structure of Cotylaspis insignis Leidy, 
from Lake Chautauqua, New York, U.S. A. 
By 
Henry Leslie Osborn in Saint Paul, Minnesota. 
With Plates 13—15 and 1 figure in the text. 
Table of Contents. 
a) Introduction. 
b) Distribution. 
c) Habits. 
d) External anatomy. 
e) The Cuticle. 
f) The Musculature. 
g) The Parenchyma. 
h) The Alimentary System. 
i) The Excretory System. 
k) The Nervous System. 
1) The Marginal Organs. 
m) The Reproductive System. 
I) general statement. 
II) the male organs. 
III) the female organs. 
n) Anatomy of very young individual. 
o) Summary. 
Note. The present article is a revision and considerable extension of 
one submitted to the American Journal of Morphology, and accepted for 
publication. It did not however appear in that journal as the journal 
was discontinued before reaching this article. As there seemed no pro- 
spect of immediate activity on the part of the Journal of Morphology this 
article has been published in its present form. 
