of the Families Lophogastride and Euphausiide. 455 
specific name TZ. borealis must yield to the later name 
Nematoscelis megalops, G. O. Sars. 
In 1887 Professor M‘Intosh first recorded Thysanoessa 
tenera, G. O. Sars (=T. longicaudata, Kroyer), as British 
(Ann. & Mag. Nat. Hist. ser. 5, vol. xix. p. 140). 
Lastly, Boreophausia inermis, Kréyer, was first published 
as British by Messrs. Brook and Hoyle in their paper “ On 
the Metamorphoses of British Huphausiide” (Proc. Roy. 
Soc. Edinb. 1888, p. 414). 
Such were the first records of the species of Lophogastride 
and Kuphausiide which at the present time are known to live 
in our seas. As there is no account of them in any English 
work, and I consequently have specimens frequently sent 
to me to name, I have thought it desirable to write the 
following notes on this interesting group of oceanic Crusta- 
ceans, which are found either as surface swimmers or in deep - 
water at some distance from land. 
The descriptions of the families are in great measure con- 
densed and slightly modified from the works of G. O. Sars. , 
Synopsis of Families, Genera, and Species. 
Suborder SCHIZOPODA. 
Legs furnished with exopodites used for swimming. In 
rare instances the first pair of legs formed for prehension, more 
usually this pair, as all the remaining legs, are simple. Ova 
borne below the carapace between the posterior pair or pairs 
of legs, usually enclosed in a marsupial sac formed by leaf- 
like processes which are developed from the base of the legs. 
Fam. I. Lophogastride. 
Maxillipeds robust; the exopodite imperfectly developed, 
consisting of a single joint; the epipodite very large and pro- 
jecting within the branchial cavity. First legs with ter- 
minal joint obtusely rounded, and densely hirsute ; remaining 
legs having a well-developed nail. Branchie arborescent, 
complex, the largest branch freely projecting beneath the 
body, the remaining branches concealed by the carapace. 
Marsupium composed of seven pairs of plates. Caudal limbs 
(pleopods) well developed in both sexes. No phosphorescent 
organs. Inner uropods not furnished with an auditory appa- 
ratus at their base. Telson very large, in general form 
as in the Macrura. 
