97 



In the larger of these, an egg-laden female, the rostrum (which has the tip 

 broken off) is 36 millim. long, the carapace 17 millim., and the abdomen 51 

 millim., measured in the middle line. 



Regd. No. . 



52. ? Pandalus (Plcsionika) uniclens, Spence Bate. 



? Plesionika nnidens, Spence Bate, Challenger Crustacea Macrara, p. 648, pi, cxiii. fig. 4. 

 Plesioniku afiinis, Anderson, Ann. Mag. Nat. Hist., April 1899, p. 285. 



Two young specimens, believed to be this species, were taken in the Anda- 

 man Sea, in 172-303 fathoms. 



The posterior half of the 3rd abdominal tergum is carinated in the middle 

 line. The rostrum, which is serrated dorsally at its proximal end only and is 

 more or less serrated ventrally, has a characteristic spine near the tip, on the 

 dorsal border. 



T, , -v,- 31 66-31 67 



Regd. No. - . 



53. Pandalus (Plesionika) alcocki, A. R. S. Anderson. 



Pandalus alcocki, Anderson, Journ. Asiatic Soo. Bengal, Vol. LXV. pt. 2, 1696, p. 92. 



ILLUSTRATIONS OF ME ZOOLOGY OF THE INVESTIGATOR, CRUSTACEA, PLATE LII. FIG. 2 <f, FIG. 4 ?. 



Differs from P. martins only in the following characters : 



The rostrum is of the same general shape and nearly as long : it is armed 

 dorsally, at its basal end, with (usually) 5 teeth, three (or four) of which arc 

 movable and very small and stand close together on the gastric crest, with two 

 large isolated ones just in front of them: ventrally it is armed throughout, 

 beyond the antennular peduncle, with a series of distant teeth not concealed by 

 o to the number of from 4 to 8. 



The 6th abdominal tergum is not quite twice as long as the 5th. The telson 

 is shorter than the endopodite of the caudal fan. 



There is no distinct ocellus on the dorsal margin of the eye. 



The first pair of legs are not shorter than the external maxillipeds. The 

 Mvond pair in the male alone are very slightly unequal in length: one of them 

 vouches almost to, the other very slightly beyond, the tips of tin.- external 

 maxillipeds; their chelae have no conspicuous tufts of seta? : in the female both 

 of them reach just beyond the tip of the antennal scale. 



In the last 3 pairs of legs the spines on the posterior border of the merus 

 are reduced, respectively, to 4, 2 or 3, and 2, placed at the distal end only: in 

 the female the dactylus of these legs is short, very weak, and almost completely 

 hidden in a tuft of setce. Colour in life, red. 

 13 



