324 Records of the Indian Museum. [Vou. XI, 
from a large number of European freshwater fishes, such as Tinca 
vulgaris, Gasterosteus spp., Cyprinus carpio, Esox lucius, Perca 
fluviatilis, Salmo trutta, etc., and even from the tadpoles of 
frogs. 
The parasites attach themselves to their host by means of two 
strong suckers which are the modified anterior maxillipeds. Like 
other parasitic Copepoda they suck the blood of their host. 
This is effected by means of a proboscis or dart which is evertable, 
and which is formed by a modification of certain of the mouth 
parts. The posterior maxillipeds are also modified for the purpose 
of clasping, and thus enable the parasite to cling to its host. In 
addition, the basal joints of the anterior antennae are modified for 
a similar purpose. The parasites lie inserted between the scales of 
the fish, with their long axis parallel to that of the host. They 
are, however, by no means stationary and fixed, but may be seen 
to skip about over the fish’s body as if in search of a better posi- 
tion. During the breeding season they voluntarily leave the body 
of the fish and swim about actively in the water by means of four 
pairs of swimming legs. Unlike other Copepoda, the eggs, which 
are laid in gelatinous strings of two rows, are usually shed into the 
water and not carried about by the female. On being shed, the 
gelatinous covering hardens and thereby firmly attaches the eggs 
to the object on which they were deposited. Observations made in 
Europe show that the parasite breeds three times a year. Under 
these circumstances it is clear that there are three occasions each 
year when infected fish may free themselves from their parasites. 
The development of the egg occupies about a month. 
Wilson states that the newly-hatched larvae have the general 
characters of the adults and on hatching begin to swim at once. 
The nauplius, metanauplius and early cyclops stages are passed 
inside the egg. After a few moults they become adult. Certain 
species of Avgulus appear to be capable of living on both fresh 
and salt water fishes. This circumstance, together with the fact 
that the parasites can swim freely and frequently leave their host, 
accounts for the fact that the same species of parasite is often 
found on different species of fish. 
As far as I am aware this is the first definite record of this 
parasitein India. In April, 1910 Mr. S. W. Kemp, Senior Assistant 
Superintendent, Indian Museum, inspected a tank near the palace 
of the Maharaja of Cossim Bazar in which diseased fish (Rohu, 
Labeo rohita) were living. He found that the disease was associated 
with scanty food, and the presence of large numbers of leeches 
and parasitic Copepoda, the latter belonging to the genus Argulus. 
On April 17th, 1911, Dr. Annandale obtained a free-living 
Argulus from the Atrai river, near Siliguri, at the base of the 
Himalayas (Jalpaiguri District, Bengal). I have examined the 
latter specimen and found it to be a very small male Argulus 
foliaceus, Linn. Unfortunately I have been unable to obtain the 
specimens collected by Mr. Kemp, but it is very Se ae that 
they also belong to this species. 
