394 
CRUSTACEA. 
coloured ” spots. Each segment of the body in every specimen examined 
(about thirty in number) is marked with a round black spot, whence, in 
some, arborescent arms branch off ; in others there is no arborescent 
appearance, but the segment is dotted regularly over with extremely 
minute points. 
M. vulgaris , J. V. Thomp. 
On the occasion mentioned my attention was first directed by remarking 
among those captured, individuals wanting the black spot on the segments 
of the body, when, singling out three of these, they proved to be of this 
species — all the others were 31. Chamceleon. The segments however ex- 
hibit an arborescent veining, though wanting the black central spot. 
These specimens are one inch in length, or one-fifth less than the largest 
31. Chamceleon taken with them. If the proportion of the one species to 
the other in the myriads seen were as in those taken, the numbers of 31. 
vulgaris to the other were but as one to ten. Some of these (31. vulgaris) 
produced young in the phial, like those represented by Muller in the 
Zoologia Danica, pi. 66, and by Kroyer in the Voyages Scandin. et 
Lapon. Crustaces, pi. 9. 
Ballyhome, Belfast Bay, July 4, 1846. — From the rocks at the entrance 
of this bay I captured in pure sea-water a number of the 31ysis of various 
sizes, all of which proved to be 31. Chamceleon. The extraordinary differ- 
ence in colour of these specimens, all taken together within the space of 
a few yards, well justified the specific name. They were brown, green, 
pink, red, and hyaline, some as transparent in colour as the water itself ; 
a few displayed a whitish longitudinal stripe down the back. With the 
view to a more particular examination of the colours at home, they were 
placed in a phial of sea-water, but were all dead on my arrival there a few 
hours afterwards. Of the many species of the more minute forms of 
Crustacea which I have preserved in spirits, the 31ysidce were always 
among the first to become soft and to decay. The specimens under con- 
sideration, when examined in spirits, exhibited on each segment of the 
body a black spot, whence more or less of an arborescent appearance w'as 
manifest. 
31. Chamceleon has occurred to me much more frequently as well as in 
greater numbers on the Irish coast than 31. vulgaris. In very shallow 
pools between tide-marks at Lahinch (Co. Clare) the latter was procured 
by Professor E. Forbes and myself. It frequents the tidal river Lagan 
at Belfast. 
Genus Scorpionura. 
S. vulgaris, Thomp., J. V. 
South of Ireland. 
S. longicornis, Thomp., J. V. 
South of Ireland. 
S. maxima, Thomp., J. V. 
South of Ireland. 
Genus Cynthia. 
C. Flemingii, H. Goodsir. 
Among some of the more minute Crustacea taken at Strangford Lough 
in May, 1840, by Mr. 11. Patterson, is a Cynthia, but hardly sufficiently 
