204 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
spot distinguish this species from the others of the genus. 
Westwoodia nobilis, Baird. (Pl. XX XIII, fig. 4.) 
Length 1. mm. Occasionally found in rock pools at 
Hilbre and Puffin Islands. The one jointed inner branch 
of the feet of the first pair at once distinguishes this species. 
Harpacticus chelifer, Niuller; (Pl, XXOxomn iosras) 
Length 1.25 mm. Common throughout the district as 
a free swimmer and in dredged material. The chelifate 
posterior foot jaw (c) clearly distinguishes this species. 
Harpacticus fuluus, Fischer. (Pl. XX XIII, fig. 6.a.6.¢.) 
Length 1.25 mm. Abundant in rock pools at Puffin 
Island, generally of a bright red colour and very conspicu- 
ous on the green alga Hnteromorpha. 
Prof. Herdman’s experiments as to the capacity of this 
crustacean to adapt itself to various degrees of salt and 
fresh water are given in Report III of the Marie Biologi- 
cal Station on Puffin Island, 1889, p. 36. 
Harpacticus flexus, Brady & Rob. (PLXXXIL fig. 6.d.e,f.) 
Length 1.25 mm. Very similar in general appearance 
and characters to H. chelifer, but smaller and recognizable 
by the second foot jaw which is slender and without the 
excavated toothed hand so characteristic of that species. 
ZLaus spnatus, Goodsir. (Pl. XXIII, fig. 7.) 
Length 0.65 mm. A pretty minute species frequently 
found in tidal pools at Hilbre and Puffin Islands, &c. ; 
also dredged in Port Erin Bay. 
Zaus goodsirt, Brady. (Pl. XXXIII, fig. 8.) 
Length 1.30 mm. Dredged off the Calf of Man in 20 
fathoms and off the Little Orme, and in Colwyn Bay. 
In some of the specimens from the first locality the three 
central body segments are of a brilliant crimson colour. 
Alteutha depressa, Baird. (Pl. XXIV, fig. 1. ¢.) 
Length 1.30 mm. Common throughout the district, 
chiefly a littoral species, also frequently found in the night 
