50 BULLETIN 97, UNITED STATES NATIONAL MUSEUM. 



Chelipeds short and stout. Dorsal aspect of carpus subtriangnlar. 

 Manus more or less crested above, the upper proximal angle often 

 very prominent. 



Legs slender and smooth. 



First segment of abdomen covers the sternum ; the second is much 

 shorter, exposing the sternum ; the third does not reach the coxae of 

 the fifth pair of legs; third, fourth and fifth segments coalesced. 



Restricted to America. Analogous species on opposite sides of the 

 continent: smithii (Atlantic) ; pugnax (Pacific). 



KEY TO THE SPECIES OF THE GENUS GLYITOPLAX. 



A 1 . Lateral margin with five teeth, orbital angle included pugnax, p. 50. 



A*. Lateral margin with four teeth, orbital angle included smithii, p. 51.' 



GLYPTOPLAX PUGNAX Smith. 



Plate 158, figs. 1-6. 



(jlyptoplax pugnax SMITH, Trans. Connecticut Acad. Arts and Sci., vol. 2, 

 1870, p. 1G5 (type-locality, Panama; type in, P.M.Y.U.). A. MILKB 

 EDWARDS, Crust. Reg. Mex., 1SSO, p. 335, pi. 61, figs. 5-Sf. 



Diagnosis. Five side teeth, the last one large. No lobe on upper 

 edge of palm. 



Description. Carapace slightly convex longitudinally, not at all 

 transversely; thickly granulous. Mesogastric lobe separated from 

 the prominent protogastric lobes. The epigastric lobes are slight ele- 

 vations separated by a marked median sulcus. Hepatic region promi- 

 nent, set off by deep sulci. Mesobranchial and metabranchial lobes 

 separated by a very slight sulcus, while the anterior portion of the 

 branchial region is divided into three lobules, one at the base of the 

 epibranchial tooth, a large one just within this, and a small indis- 

 tinct one next the gastro-cardiac sulcus. 



Front thin, horizontal, edge slightly convex, a small median notch. 

 Inner angle of orbit a prominent tooth ; two deep notches on upper 

 border. Antero-lateral margins arcuate; the outer angle of the orbit 

 projects only slightly beyond the second tooth and is separated from 

 it by a slight sinus. In addition, there are three prominent triangu- 

 lar teeth, of which the middle one is most prominent. 



Chelipeds slightly unequal, hands very large. Merus not project- 

 ing beyond carapace. Carpus short, outer face granulous, a slight 

 groove along the margin next the propodus, a tooth on inner margin, 

 and a small tubercle near articulation of propodus. Hand com- 

 pressed, very broad, and nearly smooth, lower edge rounded, upper 

 edges lightly crested. Pollex very broad at base, much deflexed, lower 



1 Glyptoplax pit a ill a (Rathbun), 1809,JI/icroponope putiUa A. Milne Edwards, 1880, 

 I have placed In the Family Xanthldae. 



