62 



Cumacea: 4. Ceratoeumatidae, 1. Ceratocuma, 5. Leptocumatidae 



^ 



1. C. horridum ('aim. 1905 C. horriJa, Caiman in: Sci. Invest. Fish. Ireland, 

 1904 app. 1 p. 11,37 t. 4 f. 57— 75 | 1912 C. horridus, T. Stebbing in: Ann. S. Afr. 

 Mus., u lOv p. 143. 



Pseudorostral lobes horizontal, bluntly truncate, meeting for a moderate 

 distance in front of the small eyeless eyelobe; a rather deep sinus is formed 

 by the bifid antero-lateral corner produced as far forward 

 as the pseudorostrum, the lower tooth initiating a long 

 lateral ridge on the dorsally flattened carapace. This is 

 diversified by 1 1 pairs of nota))le procurved teeth, 3 pairs 

 submedian, the rest lateral. All five pedigerous segments 

 are free, each except the first carrying a dorsal and a 

 lateral pair of spine-like processes, the lateral pairs of 

 the second and third segments being expanded at the 

 base and hollowed beneath to receive the end of the 

 flagellum of the second antenna. Fifth pedigerous segment 

 without trace of limbs, having ventrally behind a median 

 spine 2 contiguous eminences with the crescentic slit-like 

 apertures of the vasa deferentia. The first 4 pleon seg- 

 ments have each a pair of blunt recurved teeth at the 

 rear; the 5*^ segment is nearly three times as long as 

 the sixth; the little round-ended telson becomes inconspicuous 

 when closed down over the anal opening. Antenna 1 has 

 the 1^* joint large, distally Avidened, the flagellum 4-jointed, 

 accessory 1-jointed, both provided with sensory hairs. 

 Antenna 2 with last joint of peduncle nearly twice as 

 long as the preceding joint. The fully adult character 

 of both antennae makes it improl)able that the absence 

 of the 5^^ peraeopods is due to immaturity. Mandibles 

 with strong molar and numerous spines. Palp of maxilla 1 

 with 2 filaments. Maxilliped 1 with the epipod scantily 

 provided with branchial leaflets. Maxilliped 2 with full 

 number of joints. Maxilliped 3, the long 2°'i joint nar- 

 rowed distally, not apically produced. Peraeopod 1 has 3^ 

 joint longer than 4*^ 5*^^ equal to both combined, the 

 short e,^^ furnished with 2 peculiar processes each armed 

 with a dense tuft of radiating setae. Peraeopod 2 very 

 slender, the long 2°'^ joint narrowing rapidly about the 

 middle, the 5*^ joint much more than twice the 6*^ and 

 7th combined. Fifth and sixth joints much longer in the 

 €.iiorridum((j)Caiman. 4*1' than in the 3'^ peraeopod. Pleopods feebly developed, 

 in the South African specimen only the first pair clearly dis- 

 cernible, although the antennae evince maturity. Uropods two-fifths of body's 

 length, the subequal rami more than thrice as long as the peduncle, each serrate 

 on medial margin, tapering to a fine point, with minute terminal spine. L. 4-05 mm. 



Irish Sea, 77 miles W. N. W. of Achill Head, county Mayo, 699 m; South Africa, 

 €ape Natal N. by E. about 24 miles, depth 805 m. 



Fig. 25. 



5. Fam. Leptocumatidae 



1912 Leptocumatidae, T. Stebbing in: Ann. S. Afr. Mus., v. lOv p. 133. 

 Telson wanting. Accessory flagellum of antenna 1 very small. Antenna 2 

 of 9 3-jointed. Palp of maxilla 1 ending in 2 filaments. Peraeopods 1—4 



