Ho.1653. PACIFIC COAST COPEPODS WILSON. 459 



Total length, LO mm. Length of head, including the anterior 

 processes, 2.35 mm. : of genital portion, I nun.; of o«r^ strings, 13 mm. 

 Width of head. L.35 111111.; of genital portion. L.45 nun. 



Color. — (preserved material) a uniform light chocolate In-own. the 

 processes on the head yellowish white, the egg strings a light tan color. 



{medu8ceu8, medusa-like, alluding to the mass of anterior proc- 

 esses on the head. ) 



Genus OPIMIA, new. 



Diagnosis. — General form elongate and slender; head swollen into 

 a globe or sphere, smooth and without processes; neck- cylindrical and 

 two-thirds of the entire length; genital segment narrow, three times 

 as long as wide, and carrying posterior processes; abdomen very 

 short and rudimentary. 



Mouth terminal, upper and under lips protruding; mouth parts 

 reduced to finger-like projections; second maxillipeds well developed 

 and evidently used for prehension. Only one pair of swimming legs 

 clo-c behind the maxillipeds. Male unknown. 



Type-spi ties. — Opimia < xilis. 



(Opimia, a vestal virgin who proved unfaithful to her vow and in 

 bonsequence was buried alive. ) 



OPIMIA EXILIS. new species. 



Plate LXXVI, figs. L02 to mi. 



Host and record of specimens. — Two females were obtained by 

 Doctor McClendon from the common soup-fin shark, Galeorhinus 

 syopterus, at La Jolla, California. They are made types of the 

 genu- and species and are Cat. No. 38601, Q.S.N.M. 



Female. Cephalothorax orbicular, considerably swollen, with the 

 mouth tube and mouth parts projecting from its anterior margin; 

 it- surface smooth and uniformly rounded, without any trace of lob'es 

 or processes. Free segments developed into a neck two-third- of 

 the entire length and about two-fifths of the diameter of the cephalo- 

 thorax. This neck is straight, smooth, and free from wrinkles 

 except at the very base where it joins the genital segment. The 

 latter widen- gradually to the same diameter as the cephalothorax. 

 At it- anterior end it is wrinkled similar to the adjacent portion of 

 the neck: at its posterior end it is thrown into two or three much 

 larger folds, but is smooth through the center. Attached to it- pos- 

 terior margin, a little nearer the dorsal than the ventral surface, are 

 two -lender cylindrical processes. Bach is one-third the diameter 

 of the genital segment and nearly straight, so that the two extend 

 hack side by side and look like short egg strings. Between them 

 and on the extreme dorsal margin is the rudimentary abdomen, which 

 consists of little more than a pair of tiny papilla 1 or knobs, represent- 



