Solenogaster Mollusks— -SCHWABL 
273 
FIG. 18. Crystallophrisson nitidulum var. pacifica. 
Sta. 2418. 
Crystallophrisson nitidulum (Loven) 1844, 
stem species 
Crystallophrisson nitidulum var. pacifica n. 
var. 
Figs. 16-18 
COLLECTIONS: 
2121 (1) in 32 fm, with C. sp. 
2168 (1) in 12 fm. 
2176 (3) in 28 fm. 
2417 (1) in 34 fm, with C. sp. 
2418 (2) in 185 fm, with Limifossor fratula 
and C. scahrum. 
2614 (2) in 155 fm. 
2457 (1) in 111 fm. 
2743 (1) in 150 fm. 
3204 (1) in 115 fm, with Limifossor fratula. 
3205 (1) in 88 fm, with C. sp. 
the radula and particularly large lateral ones 
extend from the radula to the junction of the 
fore-gut with the mid-gut. The radula is large 
and highly chitinous but without denticles. It 
extends far into the lumen of the fore-gut 
and has unusually large supports. The mid-gut 
and rectum are spacious. The pericardium is 
not very wide but extends far proximally. The 
ventricle is muscular and has two atrioventri- 
cular openings. The dorsal vessel begins with 
a bulb. The epithelium of the gonoducts con- 
tinues for some distance on the wall of the 
cloacal chamber. 
DISTRIBUTION : All specimens come from 
the San Pedro area, southern California, and 
all but one from depths between 310 and 446 
fm. Eleven, or 78.5%, are from mud, and 5, 
or 35.7%, from glass sponge areas. 
Fig. 17. Crystallophrisson nitidulum var. pacifica. 
Sta. 2176. 
