118 
97A. 
97B. 
97C. 
99A. 
99B. 
100. 
101. 
CALIFORNIA ACADEMY OF SCIENCES. 
PLATE Xb Ete 
ECLIPIDRILUS FRIGIDUS. 
Cross-section of the neck of a nephridium. 
Section of the long duct. 
Nephrostome and part of duct. 
Section of the lower part of the male organ, slightly oblique to the longitudinal axis of the penis, but parallel 
to the atrium. air. atrium. (/f.¢. fibrous tissue. in. inmer lining of the atrium with long oval nuclei. 
1. ms. longitudinal muscular layer of atrium. ¢. ms. transverse muscular layer. gl. small glands scattered 
over the surface of atrium and prostate. spd.spermduct. sep. part of the septum between x/xi. sph2t. cir- 
cular muscles or sphinxter. g/l. c. large glandular cells composing the collar. m. p. muscular plates, to which 
the longitudinal muscles of the atrium are joined. tube. penis tube. ps. penis sheath. pre. preputium. 
bd. body-wall. i 
Section of inner penis tube of the former figure. 
The lower end of the male organ, atrium and prostate in somite x, xi, somewhat diagrammatically figured, in 
order to show the different layers, penis, ete. pr. prostate proper, projecting somewhat into x. s. septum. 
1. pr. terminus of prostate. pr. m. muscular layer surrounding the prostate. This layer contains numer- 
ous glands. pr. gl. glandular layer of long flask-like cells. ep. inner lining epithelium. tube tube running 
from prostate through penis and atrium—a penis lumen, with thick walls connected with the atrial wall by 
numerous strands, which on the upper part form a thick layer surrounding the tube, but lower down becomes 
thin, at least consisting of only few strands. col. collar surrounding posterior part of penis. p. penis, 
projective part. pre. preputium, eversible. bd. body-wall. /f. ¢. fibrous tissue. 
A somewhat larger view of the lower end of the penis. Both this and the former drawing are made from 
dissections mounted in gum-thus and yiewed from above. Letters indicate the same as in fig. 92. 
