SIPHONOSTOMATA. 
409 
The eye itself, under the lens or microscope, exhibits constant motion, 
and even to our unassisted vision its red colour — that of the lady-bird, 
Coccinella septempunc- 
tnta — is apparent ; / 
when magnified it / 
looks black where the / / ^ 
lines and dots are, red / (^5) \ 
elsewhere. ' 
After having been about four or five hours in the salt water, and dis- 
playing its wonted activity to the last, the specimen was lost during my 
absence from the room. I had intended to observe how long it — a fresh- 
water species — would live in salt water, but though foiled in this, have 
thought these notes, made with the living animal before me, might per- 
haps be worth the room they occupy, more especially as the Argulus 
seems to be very little known as a British species. From what has been 
stated it would seem to be very tenacious of life. The individual here 
treated of is the second Irish one I have seen ; the other was, when 
swimming freely in Lough Neagh, taken by Mr. Hyndman in the autumn 
a few years since. Like the present specimen, it displayed a mass of 
large ova. 
Genus Caligus. 
C. Mulleri , Leach. 
“ North of Ireland,” Mr. Templeton. 
C. salaris f J. V. Thomp. 
“ South of Ireland,” J. V. Thompson. 
C. scombri, J. V. Thomp. 
“ South of Ireland,” J. Y. Thompson. 
C. productus, Mull. 
“ North of Ireland,” Mr. Templeton. 
Belfast Bay, W. T. 
C. minutus, Otto. 
I obtained a specimen off a holibut in Belfast market in February, 
1837. It differs very little — hardly in species— from C. hippoglossi, Kroyer, 
Tidssk. hind i. p. 625, pi. 6, f. 3 (1st series). 
M. Edwards notes the species as found on the coast of Bretagne in the 
branchial cavity of the “ Bass | [Basse. Labrax lupus, Cuv.]. 
C. diaphanus, Nor dm. 
Nordmann obtained this species off Trigla hirundo. I have procured 
it not only on that fish but on the following, purchased in Belfast market : 
— Trigla pini, Pagellus centrodontus, Scomber scombrus , Caranx trachu- 
rus, Merlangus carbonarius, Merlucius vulgaris, Lota molva, Platessa vul- 
garis, and Pleuronectes maximus. The specimens were taken in March, 
August, October, and December (1837). 
C. Stromii, Baird, 
I have found on Salmo trutta taken in Dundrum Bay (Co Down), Aug., 
1836, and on the same species cajffured in the sea at Donaghadee in 
March ; on Salmo eriox from the latter locality in Dec. ; on Salmo salar 
taken on ascending two of the Co. Antrim rivers from the sea in June 
