23^ 



very small. incnliat(ir\' laiiiclhc lik'pwise .-miall. lancpolati', with diih' I'cw iiiarf^-iiial 

 setsp. TpIsou ratliiT lirnad, I'dniuled at tlic tip. 



Beiiiarks. — Tlie ])vpseiit gemi.-; is eliietly distiiio-nislird frnm Orrlicstin 

 by tlip anterior giiatliopoda being simple, not snbolieliform, and the jiosterinr 

 ones being exactly alike in the two sexes; moreover by the less cdniiiressed 

 form of the bfidy. It romprises only a few species, the validity of which 

 would moreover seem to be rather ihiubtfnl. 



1. Talitrus locusta (Pallas), 

 (ri. 0). 



Onhcaf!' Inrimfa, Pallas, Spocil. Zool. fasc. 0, tal). 4, liy-. 7. 

 Syii : Tiililniit sfilft/fnr (Mont.), EiIt. 



Body compai'atively slnn't and robiist, with the coxal plates scarcely 

 as dee]i as the mesosome, 1st pair triangular, more or less covered by the 2nd; 

 oth pair neaidy as deep as the preceding ones. Ceplialon rathei' deep, trans- 

 versely truncated in front, with the bnccal mass greatly pi'ojecting. Eyes 

 comparatively small, rounded, with black pigment. Sitperior antennsp scarcely 

 reaching lieyond the penultimate joint of the peduncle of the inferior, flagellum 

 much shorter than the peduncle, 7 — S-articulate. Inferior antennfp in female 

 about three times the length of the superior, with the last joint of the peduncle 

 as long as the two preceding ones combined, Hagellum about the length of the 

 ])eduncle; in male much stronger, sometimes nearly as long as the whole body. 

 Anterior gnathopoda with the propodal joint scarcely more than half the length 

 of the carpal and slig•htl^• tapering distally. Pleop(ula with the liasal part about 

 the length of the rami and beset on the oiiter edge with slender spines. ■ Last 

 ]iair of uropoda with the ramus nearly as long as the basal part and beai'ing a 

 single slender spine at the tip and several short ones on the outer edge. Telson 

 jiearly twice as broad as it is long, with bunches of small spines dorsally. 

 (jolour, when alive, light greyish white, with dark bluish markings on the 

 back. Usual length of adult male 1() mm; that of female somewhat less. 



Remitrl-fi. — Although the description and figure given hy Pallas of 

 liis OnisCHS locusta is very imperfect, there is all reason to believe, that he 

 has had this form before lumself and according to the rules of priority his 

 specific name locxbfa ought therefore to be preferred to that of i-aZ/rt/or pro])osed 

 l)y Montagu. 



Orcnrroncc. — 1 have met with this form rather plentyfully on the 

 sandy beaches of Lister, on the south coast of Norway, where it occurred 

 near the level of sju-ing tide highwater mark, beneath old sea-weeil. Boeck 



