GAMMARIDEA. g57 



Females. — The flagellum of the inferior antennas, varies as in the 

 males, though usually shorter, as the separate joints have less 

 length ; the number of joints is twelve to nineteen. The superior 

 antennas are about half as long as the base of the inferior; the flagel- 

 lum is about five-jointed. The second pair of legs is usually concealed 

 by being folded up under the body. The fourth joint of the first pair 

 of legs is but slightly broader and longer than the hand ; the lower 

 margin is regularly arcuate and long. Hundreds were collected 

 under the sea-weed thrown up on the beach, as well as in the sand; 

 and they were exceedingly nimble in their movements. 



It is still possible that the females and males may belong to distinct 

 species. 



Talitronus insculptus, Dana, Proc. Amer. Acad. Sei. Boston, ii. 202 (male), and 

 Talitrus ornatus, D. (female) ibid., p. 201. 



Orchestia (Talitrus) brasiliensis. 



Feminae : — Corpus Iceve. Antennae inferior es dimidio corporis breviores, 

 flagello vix longiore quam basis, ferme 16-articulato, articulis parce 

 oblongis, setis paucis diametrum articuli longitudine fere cequantibus, 

 superiores perbreves dimidio basis inferiorum breviores, flagello 3-arti- 

 culato. Pedes setis perbrevibus instructi, Mis articuli bti parium 3 

 posticorum totis diametro articuli non longioribus ; pedes lmi 2dis Ion- 

 giores, unguiculati tantum, ungue crasso, curvato, parce breviore quam 

 articulus precedens ; 2di manu semi-ovatd confecti, margine manus 

 superno recto, digito minutissimo, marginali et ah apice remoto, longi- 

 tudinali, articulo Stio duplo breviore quam ±to, infra rectangulato. 

 Pedes bti Qtis dimidio breviores, Qti Imique fere cequi, articulo bto 

 angusto, setulis supernis et inferis inter se cequis, utroque margine 6-7 

 paribus. 



Maris : — Pedes lmi ac in femina ; 2di manu grandi instructi, manu 

 ovatd, palmd longd, non emarginatd nee concavd nee dentatd, spinulis 

 armatd; digito longo, ad marginis inferi angulum attingente, carpo 

 brevissimo, multo transverso, articulo 3tio rectangulato, parce oblongo, 

 nudo. 



Female : — Body smooth. Inferior antennas not half as long as the 



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