iReprinted from Annals of the Carnegie Museum, Vol. VIII, Nos. 3-4, 1913.I 



XIV. A NEW SPECIES OF THE GENUS CAMBARUS FROM 

 THE ISLE OF PINES. 



By A. E. Ortmann, Ph.D. 

 Cambarus (Procambarus) atkinsoni sp. nov. 



Diagnosis. — Rostrum concave above, with a marginal spine on 

 each side. Sides of carapace with a lateral spine on each side behind 

 the cervical groove. Areola wide, shorter than half of the anterior 

 section of the carapace. First peraeopods with long, subcylindrical, 

 slightly compressed chelae, covered with subequal, subsquamate 

 granules. Fingers about as long as palm. Third peraeopods hooked 

 in the male. First pleopods of the male of the first form with the 

 inner part pointed and setiform, but not horny, much longer than the 

 broad and blunt inner part, with a small horny spine at the anterior 

 margin. A strong shoulder on the anterior margin. Inner face 

 flattened, slightly dilated. Annulus ventralis of the female trans- 

 versely oval, slightly elevated. 



Description of male of the first form. — Rostrum concave above, 

 without median keel, margins elevated, slightly convergent, with a 

 distinct marginal spine on each side. Acumen short, triangular. 

 Postorbital ridges subparallel, terminating in a spine anteriorly. 

 Carapace slightly compressed, punctate, but not granulated. Sub- 

 orbital angle triangular, bluntly pointed. Branchiostegal spine 

 present. A distinct, sharp, but not very large spine on each side 

 behind the cervical groove. Areola broad and short, with four to 

 five irregular rows of punctations, distinctly shorter than half of the 

 anterior section of the carapace (including rostrum). Abdomen 

 about as wide as the carapace, and slightly longer. Basal segment of 

 telson with four or five spines on each side. Anterior end of epistoma 

 broadly triangular. Antennae with the flagella longer than the 

 carapace, but shorter than the whole body. Antennal scale broadest 

 in the middle. First peraeopods elongated, subcylindrical. Hand 

 elongated, slightly compressed, with subparallel margins. Surface 

 of hand sharply granulated all around, granules subsquamate, closely 

 set, and subequal. Fingers about as long as the palm, both of them 



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