THE FOSSIL STALK-EYED CRUSTACEA 27 



branchial channels meeting at middle of endostome, as in the Oxys- 

 tomes. Arm and hand elongate, triangular in cross-section, edges 

 dentate; fingers very short. 

 Miocene; Pleistocene; Recent. 



MESORHOEA IDAE.s new species 



Plate 1, figs. 5-10 



Mcsorhoea, new species, T. S. Oi-droyd, Proe. U. S. Nat. Mus., vol. 65, art. 

 22, 1924, p. 23. 



Description. — Propodus of cheliped : Inner surface of palm (pi. 

 1, fig. 8) widening from proximal to distal end, upper outer surface 

 (pi. 1, fig. 9) widest at middle, narrowing to either end, lower sur- 

 face (pi. 1, fig. 10) narrowest in middle, widening to either end. 

 Teeth of upper margin 1-i, of which tliree have a small subsidiary 

 tooth on the proximal slope; teeth of outer margin 17, alternating 

 in size; of inner margin 14 followed by two tubercles on the digit. 

 Teeth acute or subacute, in profile channeled by deep furrows except 

 toward the tips; viewed from above the teeth are seen to be thick, 

 and each is crossed transversely over its summit by a row of six 

 or fewer shiny granules. On the lower outer surface near the 

 carpus there is a longitudinal row of three granules (pi. 1, fig. 10) ; 

 also a row of granules on each of the condyles articulating with the 

 carpus. The propodal finger is bent obliquely inward, is quadran- 

 gular in cross-section, prehensile edge armed with six tubercles, the 

 first three, nearest the palm, very small, the next two large, the 

 last one, near the tip, of medium size. The outer angles of the 

 finger are also tuberculate, the line of tubercles continued well up- 

 ward on the manus either side of the dactylus. 



Merus of cheliped : Upper surface a little narrower in the middle 

 than toward the ends (pi. 1, fig, 6) ; outer surface curved (concave 

 upwards) of subequal width throughout (pi. 1, fig. 7), inner surface 

 narrow at proximal end, widening distally (pi. 1, fig. 5). Inner 

 margin with 17 teeth alternating large and small, outer margin with 

 18 smaller teeth also alternating; lower margin with 16 teeth mostly 

 alternating in size. The third large tooth from the proximal end 

 of the inner margin is more prominent than the others. The teeth 

 are granulated in a similar manner to those of the manus but in a 

 top view the teeth are narrower than on the manus and the granula- 

 tion less evident. A tubercle or large granule is on the inner surface 

 near the lower margin in the proximal third (pi. 1, fig. 5) ; in an- 

 other specimen (Nob Hill) the tubercle is on the upper surface nol 

 far behind the middle, 



' For Mrs. Ida S. Oldroyd, conchologist of Stanford Universitj'. 



