HYPER1A GALBA. 13 



GrtiERiN, Icon. R. An. Crust. \>\. xxv. fig. 5. 



WHITE, Cat. Crust. Brit. Mus. 1847 and 1850. 



Hist. Brit. Crust, p. 206, pi. xi. fig. 3. GOSSE, 



Mar. Zool. p. 139, fig. 251. 



Metocchus medusarum, WHITE, Hist. Brit. Crust, p. 207. 

 Hiella Orliynii. STRAUSS, Mem. du Museum, vol. xviii. pi. 4. 



THE head is large and rounded. The body is very con- 

 siderably dilated, while the tail is much narrowed. The 

 eyes are large and occupy nearly the whole surface of 

 the head, distinguished by an exquisite soft tint of 

 green when the animal is alive. The superior antennae 

 consist of a short peduncle (the last two joints of which 

 are shorter than the first) and a flagellum, which is not 

 quite so long as the depth of the head ; this flagellum 

 consists of a long articulus and a few faintly-marked 

 terminal articuli, but these appear to be either not con- 

 stant or only visible under treatment with liquor po- 

 tassae. The inferior antennae are scarcely as long as the 

 superior, and terminate in a flagellum nearly resembling 

 that just described. The terminal articuli are, therefore, 

 not to be depended upon as a specific character. The 

 arms are small, and differ but slightly ; the second pair 

 have the hand somewhat the longer, and the wrist some- 

 what more infero-anteriorly developed than in the first 

 pair ; both have the margin of the wrist fringed with 

 strong but not very sharp spines. The walking legs are 

 nearly of one length, and tolerably robust. The caudal 

 appendages are broad and flat, and have the rami serrated 

 at the margins. The peduncle of the last pair reaches 

 quite to the extremity of the preceding, and the middle 

 piece consists of a small lanceolate scale. 



The colour of the species, except the green eyes, is 

 fawn, or faint yellow, passing into a salmon tint soon 

 after the animal is put into spirits ; it is also dotted all 

 over with small specks of red. 



