THE FOSSIL STALK-F.YED CRUSTACEA 45 



jiclvanced but not reaching line of front. Inner angle of orbit swol- 

 len, conical. Antero-lateral teeth small, blunt, obscure, apparently 

 three in number, almost equidistant from the orbital angle and one 

 another. Basal article of antennules much swollen in the outer 

 half; narrow portion of interseptum with subparallel sides. The 

 basal article of the antennae does not reach the edge of the front. 

 Ischium of outer maxillipeds narrow behind, increasing in width 

 distally; a deep, straight, impressed line, subparallel to and near the 

 inner margin (pi. 8, fig. 2). Merus very uneven, a deep oval depres- 

 sion on inner half; a small emargination at the inner angle for the 

 palp; otherwise quadrangular. Sternum rather narrow; a deep ob- 

 tuse-angled groove unites the anterior bases of the chelipeds. The 

 abdomen as now folded nearly reaches this groove; terminal seg- 

 ment two-thirds as long as broad, end rounded; penult segment 

 about two-thirds as long as the last: fourth and fifth segments 

 much shorter. 



The chelipeds of the female are of moderate size, unequal. The 

 merus stretches its full length bej'ond the carapace; it is short and 

 high and rises in a conical lobe above a little distad to the middle. 

 Carpus large, longer than broad, inner angle well forward and 

 seemingly unarmed. Manus of larger cheliped shorter than carpus, 

 upper and inner surfaces convex, upper longitudinal outline arcuate. 

 Merus of legs long and narrow, oval in section; a single dactylus is 

 slender and strongly curved. 



Measurements. — Female holotype, length of body from margin of 

 front to line of attachment of second legs 25 mm., greatest width of 

 carapace 29.6 mm., width between outer angles of orbits 15.7 mm., 

 width of front 8.6 mm., distance between attachments of legs of 

 second pair 16 mm. 



Occui'rence. — Oregon: Rocky Point, 4 miles east of Yaquina City; 

 Oligocene series; one female embedded in nodule so that the under 

 side of body is exposed together with impressions of the chelipeds; 

 the other half of the nodule shows the impression of the ventral 

 surface of the body and the actual upper surface of the chelipeds in 

 part. Holotype in California Academy of Sciences. 



Relation. — I have placed this species in Eucrate on account of its 

 general shape, the small teeth, the groove on the sternum, the short 

 arms and palms. One must see the dorsal surface of the carapace 

 to place it with certainty. 



Genus COELOMA A. Milne Edwards 



Coeloma A. Milne Edwards, Ann. Sci. Nat., Zool., ser. 5, vol. 3, 1865, p. 

 324 ; type, C. vigil A. Milne Edwards. 



Carapace wider than long, fronto-orbital distance great; front 

 dentate; orbits wider than front, bifissured above; antero-lateral 



