100 CALIFORNIA ACADEMY OF SCIENCES. 



which are provided with two or three marginal fissures. Antennules 

 obliquely plicated, the laminiform basal joint capable of closing over and 

 concealing the following joints. Antennae minute, with the basal joint 

 comparatively large. Merus of the maxillipeds subtriangular, shorter than 

 the ischium, reaching nearly as far forward as the front; exognath broad 

 and nearly as long as the endognath. Chelipeds rather long; merus sub- 

 cylindrical; hand narrow; fingers acute and somewhat compressed. Am- 

 bulatory legs of moderate length, the joints not dilated; dactyls styliform. 

 The base of the abdomen in the male covers the last thoracic sternum; 

 distal portion narrowed. • 



Type. — R. ornata (Kandall). 



< Randallia ornata (Randall). 



Ilia ornata Kandall, Journ. Acad. Nat. Sci. Phila., Vol. VIII, 1839, p. 129. 



Ouiaia ornata Gibbes, Proc. Am. Ass. Adv. Sci., 1850, p. 186. 



Randallia ornata Stimpson, Proc. Bost. Soc. Nat. Hist., Vol, VI, 1857, p. 



85; Journ. Bost. Soc. Nat. Hist., Vol. VI, 1857, p. 471, PL XIX, fig. 



3; Ann. N. Y. Lye. Nat. Hist., Vol. VII, 1860, p. 69. Kathbun M., 



Proc. U. S. Nat. Mus., Vol. XXI, 1898, p. 613. 



Carapace nearly smooth, but furnished anteriorly with a few scattered 

 ' granules and a few larger granulations at the sides. A granulated intum- 



escence on the hepatic area and a blunt, granulated projection on the 

 pterygostomian regions. A small tubercle on the posterior portion of the 

 branchial region. Posterior margin of the carapace elevated, granulated, 

 and furnished with two pointed tubercles. Maxillipeds granulated, the 

 exognath considerably narrower than the endognath. Merus of the cheli- 

 peds subcyliudrical, pustulate; carpus granulated; hand long, palm 

 inflated, and granulated on the upper margin; fingers slender, sulcate, 

 generally longer than the palm, and finely dentate. Ambulatory legs sub- 

 cylindrical; propodi with acute, granulated upper margins; dactyls longer 

 than the propodi; those of the first pairs compressed; those of the last 

 depressed. Abdomen of the male narrowly triangular, acute, five-jointed, 

 the third joint longer than the two following ones. Penultimate abdominal 

 segment in the female large, smooth, convex, covering nearly the entire 

 sternum; last joint small, oblong, distally rounded. The sternal surface 

 in the female is deeply excavated and bounded by a prominent rim, against 

 which the large segment of the abdomen closes. The inner side of this 

 segment is hollowed out, thus forming a capacious chamber for holding 

 the ova. At the anterior margin of the rim is a deeply concave notch 

 which receives the small, terminal segment of the abdomen. 

 ^ The carapace is of a light color marbled with reddish patches which are 



larger in front. 

 Length and breadth of a specimen each 48 mm. 



