ARTHROPODA. 



CRUSTACEA. 

 BRACHYURA. 



Indeterminate Crustacean. 

 PL XIII, fig. 1. 



There is, in my collection, a specimen of the great chela of a 

 crustacean, possibly Paramithrax, but it is so poorly preserved 

 chat its determination is very doubtful. 



Locality. Shoal Creek, Austin, Texas. 



Genus GRAPTOCARCINUS. 



GRAPTOCABCINUS TEXANUS Roemer. 



PI. XIII, figs. 2, 3. 



Graptocarcinus texauus Roemer, 1887, Neues Jahrbuch f . Min- 

 eral, und Paleont. Band 1, Heft. 2, pp. 173-176, figs 

 'a and b, text. 



Dimensions. Length, 28mm. ; breadth, 36mm. 



Description, original someivhat modified. Cephalothorax 

 transverse oval, rounded, five-sided in outline ; enclosed by a 

 fine, raised, sharp border separating the dorsal and ventral sur- 

 faces; dorsal surface moderately convex, flattened centrally; 

 frontal bent downwards, ending in a broad, obtuse-angled, 

 pointed rostrum, divided medially by a fine, longitudinal fur- 

 row; outer margin of rostrum raised; orbits deeply cut. Sur- 

 face coarsely and thickly granulate; between the grains or tu- 

 bercles are scattered separate smaller ones. Where the tubercles 

 are not completely preserved and crumbled on the summits, 

 they appear ring-like and deepened in the centre. On the cen- 

 tral surface are two pairs of converging furrows. The fur- 

 rows of the anterior pair are longer and stronger than those of 

 the posterior. They are bent slightly inwards and converge at 

 an angle of about 130. They are deepest and broadest at 

 their outer ends. At their inner ends, they are so weak that 

 their junction is scarcely visible. The furrows of the posterior 



