REPORT ON THE CRUSTACEA MACRURA. 



(339 



lower lateral commences in the second antennal tooth and continues to the posterior 



margin of the carapace. 



The first two somites of the pleon have a small carina in the median line ; the third 



is strongly carinated and produced to a large, laterally compressed tooth ; the fourth is 



slightly carinated and produced posteriorly to a strong tooth. The fifth and sixth 



somites are smooth, and the telson is armed with four little spines on the dorso-lateral 



angle. 



Length, entire, 



„ of carapace, 



„ of rostrum, 



,, of pleon, 



„ of third somite of pleon, 



,, of sixth somite of pleon, 



,, of telson, 



Habitat— Station 200, October 23, 1874; lat. 6° 47' N., long. 122° 28' E.; 

 between the Philippine Islands and Borneo ; depth, 250 fathoms ; bottom, green mud. 

 Two specimens ; males. Trawled. 



West Indies ("Blake" Expedition). 



These specimens so closely resemble Heterocarpus ensifer, A. Milne-Edwards, 

 and Pandalus carinatus, Smith, that I do not hesitate to consider it the same 

 species ; any differences probably depend on the condensed description given by 

 the authors. A. Milne-Edwards describes it as having a median dorsal carina 

 projecting anteriorly to a rostrum that is laterally compressed, slightly elevated 

 anteriorly, and armed on the upper side with seventeen teeth and on the lower with 

 eight, which corresponds with the armature of the present specimens, and as being- 

 furnished with a third carina, which is above the other two lateral ones and much less 

 prominent. In the Challenger specimens this carina, the upper of the three lateral, is 

 very distinct from the hepatic region to the posterior margin, but wanting in front of 

 the hepatic region, although in certain lights a ridge is visible, which terminates anteriorly 

 near the middle of the orbital margin. 



There is a low, thick carina on the median dorsal line of the first two somites of the 

 pleon ; on each side of the first somite there is a small tubercle and the trace of a second, 

 and below it an elevated line, corresponding with the continuation of a carina on 

 the carapace. The third somite is laterally compressed and strongly carinated, the 

 carina commencing abruptly at the anterior margin and being produced posteriorly 

 to a large, strong tooth ; on the fourth somite the carina is but little marked at 

 the anterior margin, but gradually rises, and is produced posteriorly to a long, narrowly 

 compressed tooth, not quite so large as that on the preceding somite. The fifth and 

 sixth somites are smooth, laterally compressed, and destitute of either carina or tooth. 



