CRUSTACEA NORTH PACIFIC EXPLORING EXPEDITION l8l 



RAX IX IDEA 

 Genus COSMOXOTUS White 



287. COSMONOTUS GRAYII Adams and White 



Cosnionotus grayii Adams and White, Voy. Samarang, Crust., p. 60, pi. 

 Mil, fig. 3. 



As this curious crustacean is not fully described in the work above 

 cited, some of its more important characters will be noted here. The 

 antennas are nearly as in Raiiilia. The eyes are seated at the ex- 

 tremities of very long compressed peduncles, somewhat dilated 

 toward the base, and retractile backward into oblique orbits, reaching 

 to the antero-lateral angles of the carapax at the level of the middle 

 of the outer maxillipeds. The whole outer surface of these maxil- 

 lipeds is squamose or roughened with arcuated and ciliated lineolse; 

 but there is no oblique ciliated crest on the ischium, as in Ranilia and 

 iXotopKs; meros-joint as long as the ischium ; exognath sufificiently 

 broad and reaching a little beyond the tip of the ischium. Sternum, 

 as in Ranilia, narrow between the bases of the second pair of feet. 

 Last joint of abdomen in the female free. 



The carapax was of a palish brick-red color in life, with a median 

 line of white. Feet and inferior surface white. 



Our 'specimen of this species was caught with the "deep-sea 

 clams" on a sandy bottom in ninety fathoms, off the northeast ex- 

 tremity of Formosa, eighty miles from land. 



SCHIZOSOMI 



PORCELLAXIDEA 



Genus PETROLISTHES Stimpson 



Carapax depressed, subovate, not broader than long. Front trian- 

 gular, with a more or less undulated margin, which may be either 

 smooth or dentated. There is often a small tooth or lobe on each 

 side at the base of the triangular main body of the front. Eyes 

 rather large. The coxal joint of antennae is small, not reaching the 

 superior margin of the carapax, and often concealed beneath the 

 corner of the subhepatic shield, but sometimes its inner angle is ex- 

 posed in the form of a tooth beneath the eye. The movable part of 

 the antenna is thus not excluded from the orbit, but works freely in 



