118 



Cumacea: 11. Diastylidae, 5. Makrokylindrus 



Behind the eyelobe a central ridge, elevated at the middle, ascends to a 

 bilobed girdle which crosses the carapace a little behind the middle, each 

 lobe in its forward curve meeting a dentate carina which starts from the 

 pseudorostral processes, while from the meeting point a ridge descends, giving 

 off two divergent branches which reach the lower margin. Pedigerous seg- 

 ments 3 and 4 dorsally coalesced, b^^ rather long with postero-lateral angles 

 rounded. Pleon segments 1—3 in the d each with a dorsal pair of den- 

 ticles, the rest and all in the 9 smooth; telson cylindric till near the end, 

 sides smooth at the base, then serrate, the hinder half smooth, the truncate 

 apex carrying a pair of large spines. Antenna 1, first 2 joints elongate. 



Fig. 72. 



M. fragilis Stebbing, telson and 



uropod. 



Fig. 73. 



M. fragilis (?) Stebbing. 

 maxiUiped 2. 



Fig. 73 a. 



M. fragilis Stebbing 



maxiUiped 2. 



principal flagellum 4-jointed, accessory small, 2-jointed. Antenna 2 of 9 

 4- jointed. Mandibles with about 20 spines in the spine-row. Maxilla 2 with 

 distal plate seemingly undivided. MaxiUiped 1, branchial leaflets numerous. 

 MaxiUiped 2 with long lamina in place of vibratory fan. MaxiUiped 3, 

 2"'^ joint strongly produced, 3'^ short, 5*^ 6**^, and 7^^ equal in length. 

 Peraeopod 2 with b^'i joint very short, Pleopods of male with short rami. 

 Uropods slender, peduncle shorter than telson, endopod ^/^ds ^^ jQj^g ^s 

 the peduncle, with 7, 5, 4 spines on medial margin of its 3 joints 

 respectively in the 9, 1^* joint a little longer than the equal 2"*^ and 

 S'l combined; exopod with short l^^ joint, 2°*^ equal to P* of the endopod. 

 L. 10 mm. 



S. Africa, Cape Natal N. by E. 24 miles, depth 805 m. 



