136 BULLETIN 120^ UNITED STATES NATIONAL MUSEUM 



wide, width measured behind the eyestalks. Supraorbital arch with 

 a tubercle at summit. Postorbital tooth large, curving about the 

 extremity of the eye, tip directed nearly forward. Spine at end of 

 basal antennal segment slightly incurved. Sternum conspicuously 

 granulate or tuberculate, pubescent, deeply grooved between seg- 

 ments, a large tubercle opposite base of each cheliped. 



Chelipeds stout, shorter than first two or three pairs of ambula- 

 tories. Hand inflated, subglobular, sparsely granulate, a longitudi- 

 nal row of four or five tubercles through middle of proximal end of 

 outer surface. Fingers nearly as long as palm, triangularly gaping 

 when closed ; a large low tooth at proximal third of immovable finger. 

 Ambulatory legs slender, similar, diminishing in length from first to 

 fourth pair; dactyli moderately curved, almost smooth. 



Adult female: Smaller than male; granulation more extensive, 

 median and branchial tubercles less enlarged, rostrum shorter (at 

 the most very little longer, about one-tenth, than wide), abdomen 

 irregularly tuberculate, chelipeds slender, shorter than any of the 

 legs, palms only slightly inflated, fingers not gaping. 



Young: In the adult, the postorbital tooth is large and curves 

 partly about the eye, as in typical Pyromaia; in the 5^oung, however, 

 the postorbital tooth is smaller and more slender than in the adult 

 and is directed outward and very little forward, the dactyls of all 

 the ambulatory legs are, relative to their propodites, shorter and 

 more curved than in the adult, and armed with spinules, that is, 

 they are more prehensile. The young, therefore, are typical Ina- 

 choides. 



Variations. — Besides the remarkable variations referable to sex 

 and age, there are also variations in the width of carapace, and amount 

 and uniformity of granulation, the length of the rostrum, and the 

 prominence of the supraorbital tubercle, which may be spiniform. 

 There are two varieties which stand out noticeably by a combination 

 of characters: 



Variety A: Two large, sometimes high, median gastric tubercles. 

 Granules few. Legs unusually long and slender; first leg in male 

 between two and a half and three times length of carapace. Small 

 specimens with postorbital tooth pointing outward. Locality, near 

 the tip of the peninsula of Lower California (Cat. Nos. 21879, 21876, 

 25237). 



Variety B: Carapace short, stout, branchial regions uncommonly 

 swollen, hepatic region crowded toward the postorbital tooth. Gran- 

 ules coarse, fairly uniform in size, almost covering the carapace. 

 Rostrum broader than long. Panama Bay (Cat. No. 21875). 

 A young one of the same shape but with fewer granules comes from 

 a neighboring locality (Cat. No. 21874). 



