THE FOSSIL STALK-EYED CRUSTACEA 31 



Chile) and TJ . heUeri^ (Galapagos Islands). Both of these have a 

 tooth at the middle of the fixed linger and coarse tubercles at the 

 proximal end of the prehensile margin of the dactylus. The coarse 

 tubercles are distinctly separated, not crowded together like the 

 crenae of the fossil, nor are the tubercles arranged on a projecting 

 lobe but along the middle of the broad prehensile margin. Neither 

 of the Recent species mentioned has the lower margin of the fixed 

 finger rimmed. 



I hesitate to associate the claw here described with the narrow- 

 fronted Uca oldroydi. The latter is related to V . monilifera and 

 probably has a cheliped similar to that of monilifera and other 

 narrow-fronted species of the American coasts, with an extremely 

 broad, short palm and broad, flattened little-gaping fingers which 

 form an effective shield when held before the body. 



Genus ARCHAEOPUS Rathbun 



Archaeoptis Rathbun, Proc. U. S. Nat. Mus., vol. 35, 1908, p. 346 ; type and 

 only species, A. antennatus Rathbun. 



Sides of carapace converging anteriorly, posterior angles rounded. 

 Rostrum linear; orbits deep and wide. Basal article of antennules 

 very large, inflated, and much exposed. Buccal cavity wide (pi. 4, 

 fig. 6; pi. 6, fig. 2). Chelipeds moderate, fingers long and slender. 

 Last pair of legs very small, subdorsal and probably attached at the 

 margins of the abdomen the base of wdiich does not cover the whole 

 width of sternum (pi. 4, fig. 7; pi. G, fig. 4). 



ARCHAEOPUS ANTENNATUS Rathbun 



Plate 4, figs. 4^7 ; plate 5 ; plate 6, figs. 2-4 



? Small crab, Gabb, Palaeontology of California, vol. 2, sec. 2, 1869, p. 127, 

 pi. 19, fig. 1 ; original not extant ; Martinez, Contra Costa County, in 

 coarse-grained gray sandstone ; Cretaceous. 



Archaeopus antennatus Rathbun, Proc. U. S. Nat. Mus., vol. 35, 1908, p. 

 347, pi. 47, figs. 4-7 ; pi. 48 ; pi. 49, figs. 2-4. 



Description. — Surface punctate, uneven (pi. 4, fig. 5; pi. 5, fig. 1) ; 

 a transverse ridge across cardiac and branchial regions; cervical 

 suture well marked ; a broad H in center of carapace ; a groove parallel 

 to posterior margin defines intestinal region. Elevations granulate. 

 A conical tubercle crowns hepatic region, another on its margin; 

 four on branchial margin, the anterior the largest, the posterior next 

 in size. Each orbit is about one-fourth the anterior border of cara- 

 pace (pi. 4, fig. 4) ; its maximum height, at its middle, nearly as 

 great as its transverse width ; upper margin with a triangular tooth 

 near inner angle (pi. 5, fig. 1), a more prominent tooth at outer angle 



' Rathbun, Proc. Washington Acad. Sci., vol. 4, 1902, p. 277, pi. 12, figs. 3 and 4. 



