THE FOSSIL STALK-EYED CRUSTACEA 67 



orbital angle broadly rounded; front slightly more advanced at mid- 

 dle than at ends, edge not fully made out. Postero-lateral margin 

 sinuous, marked by a line of granules. 



Of the regions the mesogastric is very well marked except pos- 

 teriorly; from it a median furrow extends to the margin of the front. 

 A deeper furrow runs obliquely inward from the edge of the inner 

 orbital angle ; from its inner end a broad, shallow depression makes 

 an oblique arch to the fourth lateral tooth; cervical furrow also shal- 

 low. One small inner branchial lobule. Along the postero-lateral 

 margin the surface falls rather steeply. The surface is granulate 

 on the elevations; the granules are coarser on a broad transverse 

 curve (convex forward) across the branchial region from the widest 

 part of the mesogastric region to the last lateral tooth; and also on 

 two shorter and broader curves just before the middle of each pro- 

 togastric lobe. 



Measurements. — Holotype, length of carapace 7.8 mm., greatest 

 width 10.7 mm., fronto-orbital width 6.6 mm., frontal width 2.8 mm. 



Occurrence. — Washington : Railroad bluff about li/^ miles south 

 of Vader, Lewis County, about 700 feet below railroad post No, 79, 

 section 4, township 11 north, range 2 west; Eocene series; one small 

 carapace, holotype, and a right wrist of a larger specimen which 

 may belong to the same species. Holotype in University of Wash- 

 ington. 



Relation. — Compared to young G. maenas (Linnaeus), the 

 antero-lateral teeth are separated by narrower sinuses, there are two 

 sliglit transverse dorsal ridges, not developed in maenas.^ the 

 postero-lateral margins though equally convergent are sinuous in- 

 stead of straight. On the other hand, in both species the lateral 

 teeth are of similar shape and relative size, viz, the first smaller 

 than the second, the last narrow, reduced. The furrow at the inner 

 orbital angle is common to both, and the corresponding elevation of 

 the adjacent orbital region. The "median furrow is a little deeper 

 in the fossil and the inner branchial lobulation simpler than in 

 maenas. 



Wrist. — The si^ecim.en of wrist (pi. 16, fig. 10) occurring in the 

 same deposit as the type is very likely from a larger specimen of this 

 species. The article has the same general shape and inequalities of 

 surface as in C. maeiuts including a broad depression around the 

 iimer border and a corresponding elevation adjacent. The dorsal 

 aspect is wider in relation to the length than in maenas, and the 

 inner spine is elongate conical, narrower than in maenas and less 

 prismatic; the spine is finely granulate but most of the outer layer 

 which remains is much worn. Until a wrist is found attached to the 

 body, its identity can not be fully established. 



