414 Annals of the South African Museum. 



Mandible, cutting-edge 4-deutate, secondary cutting-edge bidentate, 

 spine-row with 6 spines, molar prominent, palp absent. 



Lower lip with the lobes ovate, somewhat incurved, apices rounded, 

 with a tuft of setae. 



Maxillae 1 and 2 normal. 



Maxilliped, 2nd joint longest, 3rd rather narrow, 4th and 5th broader 

 than 3rd, 6th much narrower than 5th, not strongly lobed internally, 

 7th narrower than 6th, inner plate with 2 coupling-hooks ; epipod 

 reaching to base of 5th, ovate, apex subacute, outer margin straight, 

 angular near the base. 



Peraeopods all broken off at the 2nd joint in both specimens ; the 

 2nd joint of all the peraeopods is elongate and very slender. 



Pleopod 1 in $ strongly indurated, very similar to Beddard's 

 figure of that of bacilloides, but apices of peduncles and rami not 

 prominent. 



Pleopod 2 in <$ as in Beddard's figure of that of bacilloides, but the 

 stylet apically not tapering so gradually, more abruptly acute. 



Uropod 2-jointed, 1st joint short, 2nd a little more than twice length 

 of 1st, tipped with 2 setae. 



Length: 7 mm.; breadth across broadest part: '75 mm.; across 

 narrow part : "25 mm. 



Colour: In spirit porcelain white. 



Locality: Cape Point N. 89 3 E., distant 36 miles. 700 fathoms. 

 Bottom green mud. 2 <J . s.s. " Pieter Faure." 20/8/03. (S.A.M. 

 No. A4066.) 



ILYCHTHONOS n. g. 



Body moderately elongate. Head nearly globular, not excavate for 

 the insertion of the antennae. Peraeou segment 1 not very short, not 

 embracing the head ; segments 4 and 5 not elongate, not much 

 narrower than 3. Pleon consisting of one segment only. Antenna 1 

 short. Only the basal joints of antenna 2 known. Mouth-parts 

 normal ; maudibular palp reduced and feeble, 3rd joint minute, 

 unarmed, molar well developed ; 6th joint of maxilliped not lobed 

 internally. Peraeopods 1-4 slender, increasing length, 5th joint in 

 peraeopods 3 and 4 elongate ; peraeopods 5-7 a little stouter, 

 moderately spinose. First pleopods in <$ with peduncles fused 

 basally, rami indistinct. Operculum in $ ovate, keeled, apically 

 cleft. Pleopod 2 in <$ with stylet rather stout, reaching a little 

 beyond apex of peduncle. Uropod uniramous. 



This genus is near to the typical genus Desmosoma, but differs in 

 having a well- developed molar but a reduced palp on the mandible. 



