TERTIARY DECAPOD CRUSTACEANS. 179 



Abdomen (male) subtriangular, 7 segments separate, diminishing suc- 

 cessively in width from the third to the seventh; fifth segment longest, seventh 

 triangular. 



Females: In the female the cheliped (only one is present) is smaller, the 

 propodus and dactylus more spinous, the fixed finger more horizontal. In 

 the male, the spines and tubercles of the manus disappear toward the lower 

 margin, in the female they become more numerous but smaller. In the 

 female there is not only a row of spines on the upper margin of the dactylus, 

 but a row of tubercles or granules on the outer surface. 



Abdomen of female oblong-oval, second segment narrower than first and 

 third, sixth segment longer than fifth, seventh longer than sixth. 



Variations. In comparing the 5 specimens at hand the areoles of 

 the carapace appear more sharply cut in the small specimens than in 

 the large ones. 



Genus PANOPEUS Milne-Edwards, 1834. 

 Panopeus, indeterminable species. 



Material. Distal end of the right immovable finger. From the 

 Yaqui Valley at Cercado de Mao (Bluff 3), Santo Domingo; lower 

 Miocene; C. J. Maury, collector; 1916. 



The following is a description of this specimen : 



This fragment might belong to any one of 3 common Recent species, viz, 

 P. americanus, 1 occidentalism or herbstii. 3 There is a deep groove on either 

 side not far above the lower margin, the grooves ending at the sinus above 

 the terminal tooth ; below there are 2 shallow grooves ; not far from the pre- 

 hensile teeth there is on either side a row of deep punctae. Teeth unequal, 

 only 10 preserved, and in general alternating large and small. 



Genus and species indeterminable. 



Material. Distal end of a dactylus or movable finger. From the 

 Yaqui Valley at Cercado de Mao (Bluff 3), Santo Domingo; lower 

 Miocene; C. J. Maury, collector; 1916. 



The following is a description of this specimen : 



The fragment is not bent sideways, so that it is not clear whether it is a 

 right or left finger; it is bent strongly downward toward the blunt, distal end, 

 has no grooves, but a few punctae arranged in lines; occupying less than half 

 of the prehensile edge, at its proximal end are 4 tuberculiform teeth (2 large, 

 2 small, alternating) which are situated one side of the middle. 



Family OCYPODID^:. 

 SANDOMINGIA, new genus. 



The following is a description of this genus: 



Carapace wide, wider at the antero-lateral than at the postero-lateral 

 angles; anterior margin moderately arcuate, emarginate at the outer fourth. 

 Front a narrow lobe, less than one-twelfth as wide as carapace. A lateral 

 tooth behind the orbital tooth. 



1 Saussure, Rev. Mag. Zool., ser. 2, vol. 9, p. 502, 1857. 



2 Saussure, loc. cit. 



3 Milne-Edwards, Hist. Nat. Crust., vol. 1, p. 403, 1834. 



