Solenogaster Mollusks — ScHWABL 
277 
anterior end of the body, with three pairs of 
precerebral ganglia, and the cerebrobuccal con- 
nective split off the common trunk immediately 
after leaving the brain. The fore-gut is short 
and unusually wide, with small lateral folds oc- 
curring only in the radular region. The buccal 
glands are in front of the sphincter muscle, 
and all three kinds of salivary glands are pres- 
ent, the lateral ones being notably large and 
surrounding also the junction of mid- and fore- 
gut. The radula is characteristic, large, and 
lacking real teeth; the tongue has a very stout, 
highly chitinous cuticle which on either side 
of the median toothlike structure may attain a 
thickness of 25 p. The mid-gut is narrow. The 
liver has granular cells on the dorsal wall and 
on the edge of the numerous septa. 
Reproductive organs are typical; the open- 
ings of the gonoducts are on papillae, their 
epithelium not continued on the wall of the 
cloacal chamber. The pericardium is very spa- 
cious and extends far backward; the ventricle 
is highly muscular, and there are two atrio- 
ventricular openings. 
DISTRIBUTION: Five specimens, all from the 
San Pedro area of southern California, come 
from depths of 415-430 fm, in mud. 
Crystallophrisson marinellii n. sp. 
Figs. 23, 24 
COLLECTIONS: 
2363 (1) in 429 fm, with Prochaetoderma 
calif ornicum and C. sp. 
2473 (1) in 16 fm. 
2753 (1) in 322 fm. 
2884 (1) in 190 fm. 
DIAGNOSIS: This is a comparatively large 
specimen (Fig. 24), measuring from 20-40 
mm long in a state of contraction; the greatest 
width is 3 mm in the region of the pinkish- 
white prothorax which may attain a length of 
5-7 mm. The terminal buccal plate is brown 
and rounded in shape. It has a single deep 
cleft on its dorsal side which contains the wide 
mouth opening. In alcohol the body is gray 
with a distinct pink shade. The spines (Fig. 
23) are large but weak, and have a slight keel; 
abdominal spines are very short. The dorso- 
terminal sense organ is covered with small 
Fig. 24. Crystallophrisson marinellii. Sta. 2884. 
spines. It is continuous with the opening of 
the cloacal chamber in front of which is found 
a glandular region. Except for the six pairs of 
very strong gill retractors, the muscles are 
weak. The longitudinal ones in the prothorax 
region are split up gradually into numerous 
bundles. Two pairs of dorsal and several pairs 
of lateral and ventral retractor muscles are 
present. 
The brain is located near the radular region 
and is not attached to the dorsal wall of the 
fore-gut but is surrounded by numerous groups 
of piriform gland cells belonging to the glands 
of the buccal plate. The common trunk of the 
three large connectives follows its course for 
some distance before the buccal connective is 
free. Four pairs of precerebral ganglia are pres- 
ent. The suprarectal ganglion may be sur- 
rounded by the pericardium and even by the 
atrium. Behind the mouth opening the fore- 
gut narrows conspicuously and does not widen 
