164 GEOLOGY AND PALEONTOLOGY OF THE WEST INDIES. 



Description. — This piece has the typical Eryonid form of the ischium 

 of the first cheliped, that is, it is much flattened, distally widened, and 

 proximally curved. While the segment is commonly unarmed, the 

 fossil joint has a row of irregular and immovable spines along its inner 

 margin; it has also numerous scattered punctae arranged partially 

 in lines. 



Tribe ANOMURA. 



Superfamily THALASSINIDEA. 



Family CALLIANASSID^. 



Genus CALLIANASSA Leach, 1814. 



Callianassa anguillensis, new species. 



(Plate 1, Figures 1 to 7.) 



Type locality. — Anguilla: Crocus Bay, southwestern shore; from 

 lowest 10 to 15 feet of fossiliferous marls; Anguilla formation; Oligocene 

 series; T. W. Vaughan, collector; March 7, 1914; 6965; L. I. 100 a 

 (1914). 



Holotype. — One right manus and base of immovable finger. Cat. 

 No. 166941, U. S. N. M. 



Additional material. — One right manus (paratype a) and a separate 

 piece of a finger (paratype b) from southwestern side of Crocus Bay, 

 Anguilla; 30 to 50 feet above sea-level; Anguilla formation; T. W. 

 Vaughan, collector; March 4, 1914; 6966; L. I. 100 b (1914). Cat. 

 No. 166942, U. S. N. M. 



A right (paratype c) and a left manus (paratype d) and a piece of a 

 finger (paratype e), 3 specimens in all, from southwestern side of 

 Crocus Bay, Anguilla; Anguilla formation; T. W. Vaughan, collector, 

 March 1914; 6894; L. I. 100 (1914). Cat. No. 166943, U. S. N. M. 



The following is a description of the holotype: 



The specimen is embedded in the rock so that the lower half of the outer 

 surface is exposed and a portion of the upper margin. Length through middle 

 of palm, 18.6 mm., width at posterior third, 16 mm. Lower margin a thin, 

 raised rim set off by a groove. Inside and a little below the rim may be seen a 

 row of rather large sockets opening distally. The margin is sinuous, deepest 

 near the proximal third, whence it rounds convexly upwards toward the wrist 

 and forms a gently sinuous curve to the base of the fixed finger. The surface 

 of the palm is partially covered with blister granules, which are large just 

 behind the finger and get smaller, lower, and fewer toward the proximal end; 

 they are separated by a narrow, smooth area from a few granules on the 

 distal margin along the cavity separating the fingers. Among the granules 

 there are a few punctae or sockets of which 8 widely spaced ones form a row 

 above the lower margin. The marginal rim soon fades out on the finger; the 

 upper border of the finger is edged with flattened granules. The surface is 

 chalky white. The white layer is broken off of the upper marginal portion of 

 the palm; the surface thus exposed is blunt and transversely rugose, and on the 

 inner side just below the margin and 3.7 mm. from the distal end there is a 

 curved tubercle, pointing forward; also in the same fine a spine at the distal 

 extremity. 



