172 Proceedings of the Royal Physical Society. 
univalve. JModiolaria nigra (the corded mussel) is another 
comparatively rare shell, adult specimens especially being 
uncommon. This species is represented in the collection 
by three or four young shells. Cuspidaria (Nera) is an 
interesting and peculiar genus of shells much sought after 
by collectors, and is represented in the collection by one 
species, Cuspidaria cuspidata. Pandora inequivalvis, Lyonsia 
norvegica, and Poromya granulata are also represented in the 
collection, and may be described as rare shells; for though 
the distribution of Pandora extends from the Channel 
Islands to Shetland, it is not so common as its distribution 
is wide; the same may be said of Lyonsia and Poromya. 
Lyonsia appears, however, to be more generally distributed, 
and of more frequent occurrence than either of the other two. 
BRACHIOPODA. 
Of Brachiopoda only two species occur in the collection, 
namely, Terebratulina caput-serpentis and Crania anomala. 
CRUSTACEA. 
The Crustacea are largely represented in the collection, no 
fewer than 148 different kinds having been identified,including 
species belonging to nearly all the important subdivisions. 
Though the so-called higher Crustacea are fairly numerous, 
one only calls for special remark, namely, Yantho rivulosa, 
Risso. This species is represented in the collection by two 
small specimens obtained from the deep water (80-100 fathoms) 
off Loch Buy, Mull. The claws have the distal portion of both 
fingers very dark coloured, and, moreover, the movable finger 
is also distinctly grooved, and is one of the characters that 
distinguish this species from Yantho florida. It-may be of 
interest to state that during last summer I obtained a specimen 
of Xantho rivulosa in the Moray Firth, from which it does not 
appear to have been previously recorded. 
Among the Anomura in the collection there are, at least, five 
species of hermit crabs, and of these Spiropagurus Hyndmanni 
and Spiropagurus levis may be specially mentioned. The one 
has comparatively broad hands, in the other the hands are 
more elongate and polished, and in the living animal there is 
usually a red but not very well-defined band, extending the 
whole length of this hand, and sometimes branching off to 
