NO. 2286. THE NEW COPEPOD FAMILY SPHYRI I DAE— WILSON. 58S 



Cat. No. 49758 U. S. N. M., and becomes the type of the new species ; 

 the male was cleared in clove oil and mounted. 



Specific cJiaracters of female. — Cephalothorax soft, cylindrical, the. 

 same diameter throughout, and transversely wrinkled; it is squarely 

 truncated anteriorly and surrounded by a raised margin, broken oa 

 the ventral surface but continuous elsewhere. Neck narrower than 

 the cephalothorax and fully chitinized, bearing on its anterior end 

 four profusely branched cliitin horns, arranged approximately at the 

 four angles of a S(juare. Each horn has a thick base which is im- 

 mediately divided into two branches, the division taking place so 

 close to the surface of the neck that it might be said there were eight 

 horns arranged in pairs. The branches are irregular, long, and slen- 

 der and twisted until they are more or less parallel with the neck; 

 they are bluntly rounded at the tips. Behind the horns the neck is 

 sraooth, hard, and thick-skinned, and within a short distance is bent 

 at right angles ventrally ; it is then straight and of uniform diameter 

 nnt'l just before it reaches the genital segment, where it is slightlj' 

 narrowed and joins the latter at its anterior end and at right angles 

 to the ventral surfiice. These two flexures being in the same plane 

 leave the head and anterior neck parallel with the trunk axis and di- 

 rected backwards. 



The trunk is elongate obcordate, flattened dorsoventrally, the 

 narrow end joined to the neck, the wide posterior end rounded into 

 a broad lobe on either side and slightly reentrant at the center. 

 On the dorsal and ventral surfaces are wide, deep grooves on either 

 side half way between the midline and the lateral margin. Along 

 the bottom of each groove is a row of five or six shallow pits. Inside 

 of the lateral lobes at the posterior end are the genital processes, 

 which are spherical and close to the median line, and from whose 

 inner, distal corners are given off the e,gg strings. The abdomen 

 has the form of a spherical knob split at the end by the anus, and 

 projects from the center of the posterior end of the trunk dorsal to 

 the genital processes. To its dorsolateral margins are attached the 

 posterior processes, which are stout and as long as the trunk, each 

 bearing about 75 respiratory cylinders, which increase in length 

 distally. Each cylinder is contracted where it joins the process into 

 a short filose neck, usually bent at right angles, so that the cylinder 

 trails back in the water nearly parallel with the process. The rest 

 of the cylinder is of the same diameter, is 10 to 15 times as long as 

 wide, and the free end is bluntly rounded and without enlargement 

 or division. The ^gg strings were lacking in the single specimen 

 obtained. 



In the center of the anterior end of the cephalothorax are the 

 second antennae, which are swollen, finger-like processes, somewhat 

 rpsembling those of Sphyrion^ but relatively smaller. On their tips 



