NO. 26 



NEW MYSIDACID CRUSTACEANS TATTERSALL 



II 



Antemwl peduncle extending forward to the level of the distal end 

 of the second joint of the antennular peduncle. 



Antennal scale (text fig. 5a) shorter than the first two joints of 

 the antennular peduncle, about three and one-half times as long as 

 broad, terminal joint marked ofif by a distinct suture. 



Fig. 6. — Gastrosaccus johnsoni, n. sp. a, First pleopod of the male, X 50 ; 

 b, second pleopod of the male, X 50 ; r, third pleopod of the male, X 372" ; d, fourth 

 pleopod of the male, X 50 ; e, fifth pleopod of the male, X 50 ; /, sixth and sev- 

 enth joints of the endopod of one of the thoracic Hmbs, X 50 ; (/, one of the lateral 

 setae of the sixth joint of the thoracic limbs enlarged. 



Mouth parts and thoracic Ihnhs essentially as in G. sanctus; sixth 

 joint of the endopod of the third thoracic limb (text figs. 6/ and 6g) 

 divided into 7 joints, that of the eighth limb into 12 joints, the dactylus 

 in all the limbs reduced ; basal plate of the exopod of the first thoracic 

 limb with the outer distal corner rounded, those of the remaining 

 limbs with a distinct tooth at the outer corner. 



Uropods (text fig. yb) with 13 spines on the outer margin of the 

 exopod and 2 spines on the inner margin of the endopod. 



