594 " THETIS " SCII5NTIFIC HESULTS. 



Six genera of this family are defined in " Das Tierreich," 

 and the appendix adds Etisirogenes, Stebbing, 1904. Ohevreux 

 in 1908, established an eighth genus under the name Eusirella. 



Genus EUSIROIDES, Stebbing. 



Eusiroides, Stebbing, Chall. Rep., Zool., xxix., 1888, p. 969. 

 Eusiroides, Chevreux, Comp. Rend. Assoc. Fran^,, (27), ii., 1899, 



p. 479. 

 Eusiroides, Chevreux, Result. Gamp. Monaco, xvi., 1900, p. 65. 

 Eusiroides, A. O. Walker, Rep. Ceylon Pearl Oyster Fish., ii., 



1904, p. 264. 

 Eusiroides, Stebbing, Das Tierreich, xxi., 1906, pp.345, 729. 

 Eusiroides, Walker, Trans. Linn. Soc, xii., 1909, pp. 325, 333. 



In 1899 Chevreux gave the name E. dellavallei to a Mediter- 

 ranean species which had been described by Delia Valle in 1893 

 as identical with the Australian E. caesarls. This latter species 

 and E. pompeii, also described in the " Challenger " Report I 

 have since regarded as synonymous with E. monoculoides, Haswell. 

 Delia Valle's suggestion, that Megamcera fascicidata, G. M. 

 Thomson, 1880, belongs to the present genus, is, I think, nega- 

 tived by the gnathopods, which have the wrist comparatively 

 elongate, instead of short and cup-shaped, at least in one sex. 

 In 1900 Chevreux added to the genus the little species E. sarsi 

 taken from small depths at the Azores and TenerifFe, and in 1904 

 Walker briefly described a scarcely larger species from Ceylon 

 waters as E. orchoinenipes. Along with this he found specimens 

 which he considered as a variety of E. caesaris, writing that 

 it " agrees with the type except as regards the pleon seg- 

 ments, which are not dorsally produced, and the third has the 

 hind margin only slightly convex, with but three teeth on the 

 lower third part ; the posterior angle is a rounded right angle 

 (fig. 22, pl.^). The telson is divided more than half its length. 

 Length of female with ova 8 millims." Walker in 1909 briefly 

 distinguishes a new species as Eusiroides diplonyx. 



EUSIROIDES CRASSI, Stebbing. 



Station 57. 



EusiroidttS crassi, Stebbing, Chall. Rep., ZooL, xxix., 1888, p. 



977, pi. xc. 

 Eusiroides crassi, Stebbing, Das Tierreich, xxi., 1906, p. 346. 



A female specimen, carrying several well developed young 

 ones, a])pears to agree fairly well with the oi'iginal description 



