MORE LIGHT IN THE FUTURE 417 
back to chapter xvii., page 235. Bopyrina virbi, corre- 
sponding with the figure of the young female given by 
Kossmann in the ‘ Zeitschrift fiir Wiss. Zool.’ Bd. 35, pl. 34, 
fig. 6, 1881, has been found lying across the hind dorsal 
margin of the carapace of Hippolyte varians taken at Ilfra- 
combe. From the conical mouth-apparatus protrude a pair 
of denticulate lancets, the points of the mandibles. 
Bopyroides, Stimpson, 1864. Formed for those species 
that agree in shape and structure with Bopyrus, but differ 
in their branchial features in having merely fleshy ridges 
instead of laminz, with the segments of the pleon distinct. 
See ‘ History of British Sessile-eyed Crustacea,’ vol. 1. p. 
223. 
Bopyroides acutimarginatus, Stimpson, 1864, on Hip- 
polyte brevirostris. Stimpson also thinks that Bopyrus 
hippolytes, Kroyer, should be placed in this genus. By 
Bate and Westwood that is called Gyge hippolytes (IXréyer). 
Kréyer’s species was taken on Hippolyte polaris. The 
host of the British form is not named. 
Hemiarthrus, Giard and Bonnier, 1887. The authors 
say, ‘It is impossible to leave in the genus Phryxus the 
parasites of the abdomen of Virbius and Hippolyte. These 
animals differ much from the Phryxus type, alike in the 
female and in the male, which has all the pleon-segments 
free and furnished with rudimentary limbs. We have 
established for these Bopyrians the genus Hemiarthrus.’ 
In the promised continuation of their great work on the 
Bopyridz, no doubt the obscure relations between this and 
some of the preceding genera will be illuminated. 
Hemiarthrus typtonis, Giard and Bonnier, 1890, on 
Typton spongicola, Costa. 
Hemiarthrus philonika, Giard and Bonnier, 1890, on 
Nika ediilis, Risso. 
Hemiarthrus virbii, Giard and Bonnier, 1890, on ‘ Vir- 
bius’ viridis, Otto. 
Hemiarthrus Oranchii, Giard and Bonnier, 1890, on Hip- 
polyte Cranchii, Leach (?). This and the preceding species 
auswer to what Walz has called Phryxus abdominalis, 
Kroyer. 
