594 
BULLETIN OF THE BUREAU OF FISHERIES. 
Mallomonas was found in three lakes, viz, Canadice, Conesus, and Otisco. In 
Canadice and Otisco Lakes it showed the peculiar distribution which has been noted by 
Whipple;® that is, it was found only in a middle stratum in the lake. In the former 
lake it was found almost exclusively in the 10-15 meter stratum, only a few being at 
the bottom. There was a maximum number of 2,110 individuals per liter of water at 
10 meters. In Otisco Lake it was confined to the 9-12 meter stratum, while in Conesus 
Lake it occupied only the epilimnion or 0-8 meter stratum. 
Colonies of Vorticella, attached to colonies of Anabaena or some other alga, were 
found in small numbers in Canadice, Cayuga, Conesus, and Seneca Lakes. The largest 
number was noted in a surface catch from Cayuga Lake, 13 colonies per liter of water. 
In all of these lakes except Seneca, Vorticella was confined to the upper 10 meters or less, 
a few being noted at 1 5 meters in the latter lake. 
Among the rotifers Polyarthra was the only form which was found in all of the 
lakes. It was most abundant in Cayuga Lake. One catch showed an average of 240 
individuals per liter in the 0-5 meter stratum. Next in order were Seneca Lake, with 
an average of 23 individuals per liter in the upper 15 meters, and Conesus, with an average 
of 23 for the upper 8 meters. In all cases Polyarthra was more abundant in the 
epilimnion than below this stratum. 
Anurcea cochlearis was present in all but three lakes, Conesus, Owasco, and Skan- 
eateles. It was not as abundant as Polyarthra. The largest catch showed only 53 indi- 
viduals per liter. This catch was obtained in Cayuga Lake at a depth of 20 meters. 
Seneca Lake was next in order, with a maximum number of 40 per liter of water at 5 
meters in one evening catch. In all of the other lakes no catch showed more than 4 
individuals per liter. In both Cayuga and Seneca Lakes Anuraea cochlearis was found 
chiefly in the upper 20 meters of water. 
Asplanqhna likewise was most abundant in Cayuga and Seneca Lakes. The 
maximum number of 26 individuals per liter of water was found at a depth of 5 meters 
in Cayuga Lake, while a catch at this same depth in Seneca Lake showed 15. A very 
few individuals were found in Keuka, Owasco, and Skaneateles Lakes, and none in the 
other lakes. It was confined chiefly to the epilimnion. 
Notholca longispina was present in all of the lakes except Owasco and Skaneateles. 
The largest number, 4 per liter, was found at a depth of 12 meters in Hemlock Lake. 
Conochilus was found in all except three lakes, Canadice, Conesus, and Otisco, 
but it was present in very small numbers and always in the epilimnion. 
Anuraea aculeata appeared in the catches from five lakes, but its maximum number 
was less than 3 individuals per liter of water. 
The catches from Cayuga and Seneca Lakes contained a few Ploesoma, the largest 
number being 6 per liter. 
A few specimens of Triarthra were found in Cayuga, Hemlock, and Keuka Lakes. 
In counting the copepods no attempt was made to enumerate the different species 
of Diaptomus and Cyclops separately. The former genus was represented in all of the 
Whipple, G. C., Microscopy of drinking water, p. 109. New York, 1899. 
