Tue MICROSCOPE. 55 
(See Mitt. aus der Zool. St. Neap. 5-416, 1884). The present 
species clearly belongs near Sp. sertulariarum as does Vorti- 
cella brevistyla, d’Udekem (Entz) and Vorticella rhabdosty- 
loides, Mihi. (Proc. Am. Soc. Mic., Cleveland Meeting, p. 43). 
Whether they should be placed in a separate genus, Spastostyla, 
or whether they constitute a distinct group of Vorticella I can 
not of my own knowledge form an opinion. The present 
species is, I think, undescribed. I expect to study it further on 
its return the coming spring. As spring is passing into summer 
vast numbers of them become encysted ; such numbers of them 
have been seen on Cyclops as to render their color perceptible 
to the eye as their hosts were swimming in the collecting bottle. 
These cysts are oval or nearly spherical, at first colorless, then 
brown; the surface is ornamented with numerous elevations or 
bosses; at the upper pole is a ring raised above the surface. 
(Fig. 1). 
Before the cyst begins to form the zooid’s body enlarges 
considerably, the peristome and ciliary disc are then retracted 
