74 Universily of California Publications. [ ZOOLOGY 
short or occasionally wanting. Length of body, exclusive of 
processes, about 8 mm. Test very thick and exceedingly trans- 
parent. A blunt pocket of the mantle reaching into the base of 
the long lateral processes. Branchial orifice inclined somewhat 
upward, with dorsal and ventral lips, the dorsal distinetly higher 
and broadly notched in middle. Atrial orifice nearly terminal, 
but inclined a little upward, without lps. <A girdle and half 
another of minute spines on the test encircling the branchial 
orifice, and four bands of similar processes running lengthwise 
of the animal on the dorsal surface. Body muscle bands six, 
the first interrupted on dorsum; second, third, and fourth in 
contact, though hardly confluent dorsally; fifth and sixth also 
in contact dorsally. Bands all continuous across the ventral 
side, excepting the sixth, which is interrupted. Muscles all deli- 
eate, the sixth particularly so. A single rather broad muscle 
band belonging to the branchial orifice situated some distance 
away from the edge of the opening, continuous except for an 
interruption on the ventral side. A few scattered fibres around 
the atrial orifice. Endostyle relatively short, extending back 
only to the third muscle band, consequently leaving a wide inter- 
val between its posterior end and the nucleus, somewhat curved 
and rather thick. Guill extending from a little behind the first 
body muscle band back to the nucleus. Ganglion slightly in 
front of the anterior end of the gill. Hypophysis considerably 
in front of ganglion, and from surface view wholly disconnected 
from it; rather small, somewhat triangular in dorsal view. 
Nucleus very small, ovate, situated far back, ight yellow. Chain 
of buds encircling the nucleus. Pericardium and heart so deli- 
cate as to be seen with difficulty in preserved specimens. 
Fig. 19.—S. democratica-mucronata, aggregate generation. 
