CALIFORNIA STALK-EYED CRUSTACEA. 45 



Carapace broadly triangular; rostrum triangular, subacute, not depressed. 

 Median region narrow, the flattened upper surface bounded by two granu- 

 lated ridges, which converge to a point behind. Cardiac region furnished 

 with a three-sided, pyramidal elevation, the edges of which are usually 

 granulated. Postero-lateral regions large, and furnished with an S-shaped, 

 granulated crest, which extends from near the posterior end of the median 

 region to the acute lateral angles of the carapace; in front of the anterior 

 bend of this crest there is a pair of minute tubercles. Autero-lateral mar- 

 gin straight or slightly concave in front, convex near the middle, the 

 posterior portion passing outwards and backwards, arching over the legs; 

 the teeth on the anterior part are small and irregular, but they become 

 larger posteriorly, where they are furnished with secondary denticles. 

 Postero-lateral margins transverse; posterior margin not produced over 

 the abdominal segments. Outer portion of the orbit with a superior and 

 an inferior fissure. Ischium of the maxillipeds smooth, the antero-in- 

 ternal angle produced; merus small, the surface concave and bearing near 

 the middle a prominent tooth. Chelipeds long, trigonal; the sides of the 

 merus convex, the edges sharply granulate to dentate; carpus with three 

 or four granular lines; hand about as long as the merus, the angles 

 prominent and dentate and the sides concave; pollex short, deflexed; 

 dactyl short, but longer than the pollex, and when closed its outer margin 

 is nearly at right angles to the long axis of the hand. Ambulatory legs 

 compressed, strongly carinated above; dactyls narrow, strongly sulcate, 

 and corneous-tipped. Color reddish. 



Length 18 mm.; breadth 28 mm.; length of cheliped 50 mm. 



Monterey (Dana) ; Santa Oatalina Island (Lock.)! 

 This species is quite common in Avalon Harbor, Santa 

 Catalina Island. I have examined a specimen in the 

 California Academy of Sciences which I feel confident 

 is Lockington's type of frons-acutis. 



Genus Leiolambrus Milne-Edw. 



Carapace subtriangular, smooth, with no tubercles or spines on the 

 upper surface. The median and cardiac regions are not separated from 

 each other by a deep depression, but are limited on either side by longi- 

 tudinal sulci. Front short, truncated, and armed with a small, median 

 tooth. The antero-lateral margins are denticulated and the posterior 

 margin is furnished with teeth or spines. Lateral angles of the carapace 

 prominent and acute. Orbits well defined and furnished with a fissure in 

 the upper and lower margins. Antennules obliquely plicated. Ischium 

 of the maxillipeds produced forward at the antero-internal angle; outer 



