ON THE SHETLAND CRUSTACEA, TUNICATA, ETC. 263 
the main followed the arrangement of Bell’s ‘ British Stalk-eyed Crustacea ; ’ 
but the law of priority in nomenclature is not sufficiently attended to in 
that work, and it is necessary therefore, in numerous instances, to substitute 
the earlier names under which the species was described ; and moreover so 
greatly has the study of eyen these larger and better known Crustacea 
advanced during the last few years that, of the seventy-eight species of this 
subclass here recorded, no less than thirty-one are undescribed in the 
work referred to. In the Amphipoda and Isopoda I have followed the 
general arrangement of the recently published work upon ‘ The British Ses- 
sile-eyed Crustacea,’ by Messrs. Bate and Westwood. In the Ostracoda, two 
admirable guides exist in Herr G.'O. Sars’s ‘ Oversigt af Norges marine 
Ostracoder, 1865, and Mr. G. 8. Brady’s “ Monograph of the recent British 
Ostracoda” (Trans. Linn. Soc. vol. xxvi. 1868). In the Copepoda, I have 
derived great assistance from Dr. Claus’s ‘ Die frei-lebenden Copepoden,’ and 
from the smaller memoirs by the same author. Descriptions of most of 
the remaining species in the following catalogue must be sought in the 
various papers, monographs, and works which will be found referred to in 
the text. 
Order BRACHYURA. 
Stenorhynchus rostratus (Linn.) (S. phalangium, Penn.). 5-70 fathoms, hard 
ground, frequent. 
longirostris (Fabr.)(S.tenuirostris, Leach). Afew specimens off Balta &e. 
Inachus Dorsettensis (Penn.). Very rare. One specimen in 1864, and a few 
more in 1867. 
dorhynchus, Leach. Bressay Sound, off Balta, &e. 
leptochirus, Leach. Not rare in deep water. 
Hyas araneus (Linn.), Large in laminarian zone. 
coarctatus, Leach. The most abundant of the higher Crustacea in the 
Shetland seas. 
Eurynome aspera (Pennant). Rare. 
Xantho rivulosus (Risso). One young specimen dredged (1867) near the Island 
of Balta. Small examples have been taken in Sweden by Lovén and 
Goes. 
Cancer pagurus, Linn. 
Carcinus meenas (Linn.). Remarkably large. 
Portunus depurator (Linn.). Very rare, only two specimens. 
holsatus, Fabr. Frequent. 
pusillus, Leach. Frequent. 
tuberculatus, Roux, Crust. de la Méditerranée, pl. xxxii. figs. 1-5, = 
Portunus pustulatus, Norman, Brit. Assoc. Rept. 1861 (1862), p. 151. 
This fine addition to our fauna was first procured by me in 1861, and 
has been taken every year since. It is the most abundant of the genus 
in the Shetland seas, living in 80-120 fathoms. The fact of this fine 
Mediterranean species occurring in the deep Shetland seas, in company 
with many other southern forms, which are not known in intermediate 
localities between the Mediterranean and the most northern portion of 
the seas, is highly interesting. Portunus tuberculatus is distinguished 
by its tubercular, pustulose carapace, by the acuteness of the latero- 
anterior teeth, and the great size of the posterior tooth, which is double 
the length of the preceding ones, and by the last legs having the swim- 
ming-blade furnished with a raised median line. 
