Page 184

184     Wisconsin Acadeny of Sciences, A ts, and Letters.
   (Jammarus lininaus. (Smith.)
   Found in the Great Lakes. Dr. P. R. Hoy has found it in a
clear spring brook near Racine.
   G. fasciatus. (Say.)
   This is doubtless the most abundant of our crustacea. I have
not failed to find it, in greater or less abundance, in every stream
or pool that I have examined. It is particularly numerous in
small brooklets whose beds are covered with deposits of finely
divided vegetable debris.
   Crangonyx gracilis. (Smith.)
   This species has not been found in the interior waters of the
state. It occurs in Lake Superior, and Professor Forbes finds it
in abundance in central Illinois.
   Asellus internaedius. (Forbes.)
   Abundant in stagnant sloughs and slow running brooks about
Sauk City. These Wisconsin specimens differ from the types of,
Professor Forbes in several unimportant details, especially in the
shape of the ramus of the first genital plate, and the size of the
second joint of the inner ramus of the second plate.
   Assellopsis lenax. (IHagen.)
   This species T have not seen. It is reported from Lake Superior.
   Eubranclipus uandyi. (Forbes.) Bulletin No. 1, Ill. Mus. Nat.
Hist., 1876.
   This, our largest phyllopod, was discovered in small ponds of sur.
face water at Jefferson. It was found in abundance in April, but
after a few weeks entirely disappeared. Specimens found in two
neighboring ponds, while indistinguishable in other respects, dif-
fered markedly in size and coloring. In one of these ponds in a
densely timbered lot they were small, and pale in color, while in a
pond exposed to the sun they were much larger and brilliantly
colored.
  Lirmnenis (sp.?)
  In company with the smaller Eubranchipides above mentioned
was found an apparently undescribed species of Limnetis.
have met with it in no other locality.
  Dioptornus san guineus. (Forbes.)
  This beautiful little creature is an abundant inhabitant of th
marshy pools and ditches near Sauk City.