186 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 5 



Rostral plate cordiform, not longer than broad. Submedian spi- 

 nules or denticles comparable to those of the preceding species or 

 L. mccullochae, below, wanting. 



D^. Surface of telson smooth and punctate; median area only 

 slightly raised above general surface; of the marginal 

 spines or teeth only the lateral pair is ever acute, sub- 

 medians and intermediates often no more than low 

 lobes ; no denticles ; hind margin entire except for shal- 

 low median notch. 



Posterior margins of Sth and 6th abdominal somites smooth, 

 unarmed. Rostral plate not longer than greatest width, some- 

 times shorter. Raptorial dactylus armed with 9-17, usually 10, 

 teeth, including the terminal one; female dactylus exhibits 

 secondary sexual characters maculata, p. 190 



D^. Upper surface of telson roughened, scabrous, tuberculated, 

 or even spiny to some extent; median area somewhat 

 raised posteriorly to form a low, broad, blunt elevation 

 or tooth conforming with backward slope of telson; 6 

 pairs of marginal spines or teeth well developed, sub- 

 acute to spiniform; submedian denticles well marked, 

 though broad, and more or less coalesced. 



Posterior margins of Sth and 6th abdominal somites spinulated. 

 [Rostral plate, if like scahricauda (Lamarck), about % as 

 long as greatest breadth.] Raptorial dactylus armed with 11 

 teeth, counting the terminal one. . . . desaussurei, p. 193 



A2. Telson with a transverse row of dorsal spines in addition to those of 



posterior margin. 



Ultimate segment of shorter ramus of 6th if not 7th thoracic limb more or 

 less broadly ovate. Submedian spines of telson movable. 



B^. Five more or less subequal and equidistant dorsal spines in trans- 

 verse row on telson. 



Telson rather evenly convex before transverse row of spines. Rostral 

 plate more or less squarish-rectangular, median projection and an- 

 terolateral angles each produced to form a prominent acute spine, the 

 3 spines more or less subequal. Eyestalks more or less cylindrical, 

 cornea subglobular. Raptorial dactylus with 8 teeth, counting termi- 

 nal one. Submedian denticles 3 digueti, p. 194 



B2. At least 9 dorsal spines in transverse row on telson. 



Raised median area of telson obscurely tricarinate, each carina end- 

 ing in a simple acute spine; next dorsal carina either side ending 



