20 Universitij of California Publications. [Zoology 



In the male the capitiilum of the frontal organ is more or less 

 truncated at the base and has a blunt apex ; hispid with minute 

 hairs; the three chief setae of the antennule almost equal in 

 length, the principal one bearing beyond its middle about twenty 

 pairs of small recurved hooks. The hooked appendage of the 

 secondary branch of the right antenna is bent at almost a right 

 angle near the base and beyond this is again bent abruptly, 

 forming an arch ; the end is rather sharp-pointed, with a few 

 crenulations on the inner margin ; the appendage of the left side 

 is much smaller, abruptly bent near the base, but is not bent a 

 second time ; it also ends in a rather sharp point which is erenu- 

 lated on the inner margin. The principal spine on the basal 

 joints of both secondary branches bears three pairs of long hair- 

 like processes. 



In the female the capitulum of the frontal organ is somewhat 

 larger than the peduncle; it is bent downward, has a sharp 

 pointed apex, and is hispid with a few marginal hairs. The 

 three sensory setae of the secondary branch of the antenna about 

 equal in length, nearly two-thirds as long as the principal seta. 



Length : male 2.4 ; female 2.6 mm. 



Distribution. Widely distributed at the surface and in the 

 depths of the ^Mediterranean Sea and Atlantic Ocean (Glaus) ^ 

 Pacific Ocean in the San Diego region. 



3. Conchoecia hyalophyllum Claus. 



PI. IV, figs. 3, 4. 



1891. Conchcecia hyalophyllum, Claus, p. 60, pi. VI, figs. 2-10; pi. VIII, 



fig. 9. 

 1896. Conchcecia hyalophyllum, Brady and Norman, p. 692. 



Female. — Shell rather short, about one and a half times as 

 long as greatest height ; nearly quadrangular, a little higher be- 

 hind than in front ; thin, pellucid, much compressed laterally ; 

 rostrum fairly large and rather strongly curved. 



Frontal organ slender, elongated, with very long, angularly 

 bent, sharp pointed extremity or capitulum which bears on its 

 upper margin a few spine-like hairs and on its under side twa 

 rows of the same. 



