ZOOLOGICAT, 
THREAD FISH. 
Photo by F. W. Hunt. 
would furnish some employment to the natives 
during the season when there is no work avail- 
able; the skins would represent considerable 
value, and the flesh would be available as food. 
The muskrats would also furnish a supply of 
food to the blue foxes, which are taken there in 
abundance for their very valuable skins. The 
natural food supply of the foxes has always 
been limited at certain seasons of the year. As 
the muskrat could do no harm in any way, the 
Bureau of Fisheries has favored the plan of in- 
troducing it. 
A large muskrat is about two feet from nose 
to the end of the tail. The tail is hairless and 
flattened laterally; it may be useful for swim- 
ming but so far as I have observed, the swim- 
ming is done with the hind feet, without any 
motion of the tail. 
Like the groundhog, the muskrat is credited 
with being a prognosticator; when muskrat 
houses in the marshes are built larger and 
stronger than usual, it is said to indicate a 
severe winter. An ordinary sized muskrat 
house is about five feet in diameter and projects 
from two to four feet above the water. Its 
doorways are all under water. 
SOCIETY 
BULLETIN. 641 
PRIVATE AQUARIUM. 
A letter has just been 
received from Capt. J. A. 
M. Vipan, who has a pri- 
vate fresh-water aquarium 
at Stibbington Hall, 
Wansford, England. It 
states that there are ster- 
lets now living in the 
building which were re- 
ceived in 1888; golden orfe 
and mirror carp received 
in 1883; Protopterus (the 
African dipnoid fish) re- 
ceived in 1897 and other 
interesting species. These 
are probably the best rec- 
ords in existence for fishes 
in captivity. The temper- 
ate tanks are unheated ex- 
cept in winter; the warm- 
water tanks are kept at 
75° to 78° Fahrenheit. 
Capt. Vipan has also had 
remarkable success in 
breeding exotic species in 
captivity. 
THE THREAD FISH. 
NE of the most grotesque of the fishes 
which visit our shores in the summer time 
is the thread fish, (Alectis cilaris). It is a 
southern form, generally common in Florida 
and large specimens are used for food. 
In the young the dorsal and ventral fins are 
excessively elongated and filamentous but be- 
come shorter with age. In some specimens the 
filaments keep growing even after portions have 
been broken off, sometimes being about twice 
as long as the fish itself. 
The thread fish is wonderfully iridescent and 
presents a variety of rainbow tints as it changes 
position in drifting about the tank. 
A few specimens are taken in the lower part 
of New York Bay nearly every summer, some 
of which come to the Aquarium. The species 
lives well in our tanks during the summer, but 
has not yet been carried through the winter. 
No specimens have been secured since the new 
water system was put into operation at the 
Aquarium, and it is hoped that the coming sum- 
mer will bring specimens which can be kept to 
better advantage than heretofore. 
