88 ZOOLOGISCHE MEDEDEELINGEN — DEEL II. 



Both sexes : first gnathopod subchelate *), propodite qua- 

 drangular (in 9) or with projecting hind margin (in tf). In 

 (f the hand of the second gnathopod is very large, massive, 

 suboval, with a large claw. Inferior antennae mostly shorter 

 than half the length of body. 2 



2 Second gnathopod of male with „defining" tooth at proximal 

 end of palm margin of hand, corresponding with tip of finger 

 when closed. 3 



Second gnathopod of male without such a „defining" tooth, 

 but sometimes provided at hind margin of hand with a rather 

 large falciform process at the base. 5 



3 Both gnathopods in 9 nearly equally built. Both pairs of 

 antennae in J as long as peduncle of inferior antennae. Small 

 animals of about 7 mm. length hiding beneath rejectamenta on 

 sea-shore and in shallow water. 



Htjale prevostii (H. Milne-Edwards) 

 (= H. nilssoni (Rathke)). 



First gnathopod in 9 subchelate, second gnathopod with 

 membranous, broad carpo- and propodite, dactylus extremely 

 small, placed at anterior margin of propodite, the distal margin 

 of which latter projects in a rounded projection beyond this 

 dactylus. Hand of second gnathopod in çf broadly suboval, 

 with large, curved finger. Superior antennae very much shorter 

 than inferior. 4 



4 Carpo- and propodite of last pereiopod in adult çf broadly 

 expanded ; palm margin of hand of second gnathopod regularly 

 curved, semicircular, without excavation. On the sea-shore. 



Orchestia gmnmarellus (Pallas) 

 (= 0. Utborea (Montagu)). 



Carpo- and propodite of last pereipods in adult cf not 

 broadly expanded; palm margin of hand of second gnathopod 

 with two excavations, the deeper of which occurs next finger- 

 hinge, finger with a distinct bulging portion, corresponding 

 to excavation in palm margin of hand. Living inland, under 

 stones etc. Orchestia bottae (H. Milne-Edwards) 



(= 0. cavimana Heller) 



1) Except in the female of Talorchestia briio. 



