842 THE VOYAGE OF H.M.S. CHALLENGER. 



Pleon only slightly carinated, and dorsally produced to a small tooth on the third, 

 fourth, and fifth somites. 



Ophthalmopoda longer than the rostrum ; ophthalmus small and round. 



First and second pairs of pereiopoda chelate, the second longer than the first. Three 

 following pairs of pereiopoda having meros and ischium laterally compressed, the propodos 

 long and cylindrical, and the dactylos styhform. Posterior pair resembling the preceding 

 excepting that the dactylos is short and almost lost amidst a brush of hairs. 



Habitat.— Station 120, December 9, 1873; lat. 8° 37' S., long- 34° 28' W.; off 

 Pernambuco ; depth, 675 fathoms ; bottom, red mud. One sepcimen, female. Trawled. 



The carapace is slightly compressed on the frontal crest, and anteriorly produced to 

 a rostrum that does not reach more than halfway to the extremity of the first joint of 

 the peduncle of the first pair of antennas, and has the crest armed with ten or twelve 

 small teeth. The frontal margin supports a small tooth corresponding with the first 

 pair of antennae, and, further down, a second that corresponds with the second pair of 

 antennae ; the latter is not large, but is strong and clearly defined, whence the frontal 

 margin recedes and unites with the lateral margin without forming an angle. Posterior 

 to the outer canthus of the orbit a slender, but stiff, ridge proceeds obliquely backwards 

 and then divides, one branch passing along the upper margin of the branchial region, 

 and the other and shorter branch descending to the hepatic region, where it is met by 

 another rigid elevation that proceeds from the second antennal tooth. 



The pleon is dorsally carinated, and posteriorly produced to a tooth on the third, 

 fourth, and fifth somites. 



The telson is considerably longer than the sixth somite, dorsally grooved, and has 

 the lateral margins depressed. 



The ophthalmopoda are longer than the rostrum, transversely compressed, and 

 distally carry a small circular ophthalmus and support a small tubercle on the inner 

 side. 



The first pair of antennas has the first joint depressed on the upper surface and 

 carries a scaphocerite that suddenly terminates in a sharp point ; the second and third 

 joints are short, cylindrical, and terminally support two flagella, of which the outer is 

 robust and the inner slender, both probably being a little shorter than the carapace. 



The second pair of antennae carries a broad scaphocerite of great tenuity, the outer 



