224 | Genera TTrapezia and. Tetralia. 
S Genus T'ETRALIA. 
Frons rectus aut rectiusculus, sübtilissimé denticulatus. 
Maxcillipedes externi marginem posticum valde obliqui, apicte 
articulorum secundorum inter sese paulo remoti. 
Superficies. prelabialis viaque efferens line& paulo elevatà 
divise sed margo buccalis anticus vix emarginatus. 
Pedes antici breviores, brachio apicem paulo exserto, margine. 
brachii antico apicem rotundato subtiliterque denticulato, illice 
valde deflexo. 
Pedes 8 postici, breviter unguiculati. 
Abdomen maris 7-articulatum. 
'The name 7'etralia, from the Greek verge Wm altis to the: 
subquadrate form of the specles. "Ihe Graps?lla of M'Leay, 
as shown by Krauss and others is identical with 'Trapezia. 'lhe 
want of a proper claw to the tarsus in the 'T'rapezie is a striking 
character, and is an anomaly among the Cancrinea. 'Tlhe ex- 
tremity appears truncate in a side view as well as in an upper, 
and has nothing of the texture of a claw except in its minute 
points or sete; while in 'l'etralia: the tarsus is pointed in a side 
view though somewhat truncate as seen vertically; and the - 
texture of the extremity is horny like a regular claw, which same 
texture extends back on either side. 
In the closed orbits, the antenne being wholly excluded, and 
in the ridge separating the efferent canal from the prelabial space 
as well as the narrow form, these genera are related to Eriphia. 
Fuller descriptions with many illustrations will be given in the 
Author's Report on the Crustacea of the Expedition, now ready 
for the press. 
e mmm eM m IRR 
