48 University of California Publications. [ ZooLoGy 
Body much compressed, conical, tapering from the very broad mouth 
with full lips to a narrow sensory pole. Fine network of vessels between 
meridional canals, communicating also with oesophageal canals. Gonads 
in lateral follicles of meridional canals. Rows of swimming plates reach 
almost from mouth to tip. 
Distribution. San Diego, Cal. Peru (Lesson). South Pacific 
(Mertens). Mediterranean (Forskal). 
Taken about ten miles off shore, at the surface and in vertical 
hauls from various depths to 125 fathoms with non-closing nets, 
during May, June and July. <A single mature specimen was 
taken, with the typical pointed form which is much more pro- 
nounced than in young individuals. The early stages were com- 
monly taken in considerable numbers, and resemble in shape the 
young of B. (roseola) cucumis according to L. Agassiz, and the 
adult of B. cyathina according to A. Agassiz, the aboral end 
hemispherical and the rows of swimming plates short. The 
transition to the pointed forms is gradual and convincing The 
very young are colorless, the half grown are rosy, with brilliantly 
irridescent rows of swimming plates. 
