798 



THE VOYAGE OF H.M.S. CHALLENGER. 



Observation. — This species bears a very close relationship to Palsemon beaupressii 

 of Savigny and Audouin, as well as to Palzemon petitthouarsii of the same authors. 



Brachycarpus auclouini, n. sp. (PL CXXIX. fig. 5). 



Animal robust, carapace produced anteriorly to a lanceolate rostrum, upper and lower 

 margins serrate with many teeth, of which the posterior on the dorsal surface is separate 

 from the rest and corresponds with the pyloric region ; the orbit is clearly defined, and 

 the first antennal tooth is sharp and distinct, as is also that on the hepatic region. 



The three first somites of the pleon are deeper than the carapace, the four succeeding 

 are shorter, less deep, and more compressed ; the sixth somite is only a little longer 

 than the fifth, and projects to a tooth, flanking the telson on each side. 



The telson is long, tapering, and armed with three spinules on each side. 



The second pair of antennae is longer than the animal. 



The first pair of pereiopoda is slender, small, and differing a little on the two sides. 

 The second pair has only the left limb preserved ; it is about two-thirds the length of the 

 animal, and has the propodos, including the chela, five times as long as the carpos. The 

 posterior pereiopod on the right side is the only one of the posterior three pairs that is 

 preserved ; it is slender, moderately long, and terminates in a long, sharp, unadorned 

 dactylos. 



Length 



Habitat.— Station 167a, June 27, 1874 ; lat. 41° 4' S., long. 174" 19' E.; off New 

 Zealand; depth, 10 fathoms; bottom, mud. One specimen, female, laden with small 

 ova. Dredged. 



The carapace is about one-third the length of the animal, anteriorly produced to a 

 laterally compressed rostrum, the upper margin of wdiich is in a line with the dorsal 

 surface of the carapace and a little more than half its length ; it is armed with nine 

 teeth, of which the posterior corresponds with the post-gastric region and is more distant 

 from the next than the preceding are from each other, the latter becoming gradually closer 

 and smaller as they approach the apex, the anterior being very minute ; on the under 

 margin there are six teeth, of which the posterior is the largest and the anterior the 

 smallest, corresponding in size and position with those on the upper margin. 



The frontal margin is armed with an obtuse orbital, and a sharp antennal, tooth, 



