56 THE MIcROscoPE. 
and the cystic walls begin to form. I have no doubt but that 
these cysts finally fall to the bottom and remain in the dry 
earth until autumn or the following spring. 
Another cyst (fig. 2) is of common occurrence, more partic- 
ularly on the immensely thick pedicles of Opercularia rugosa, 
Mihi. Itis probably that of a ciliate iufusorian as it is similar 
to that of Amphileptus meleagris which is also common in the 
same locality, occurring most frequently on O. nutans. The 
history of the latter cyst is as follows: The predatory Amphz- 
leptus first makes a meal of the helpless vorticellid, then 
encysts itself, usually at the extremity of the stem which bore 
its sweet morsel. The rotation of the inclosed animal may be 
readily seen through the hyaline shell which is ornamented 
with striz seen readily under a4 in. objective. After self di- 
vision there escapes two ciliate forms, like the original, except 
in size. The first mentioned of these cysts, which Claparéde 
suggests is for protection from external injuries during diges- 
tion, differs from that of J/eleagris in size and in the smooth 
shell. The contents are yellowish green, granular and may be 
readily seen alternately turning from left to right and right to 
left. An example under examination one evening showed a 
slight constriction, the same at 2 p. m. the next day had 
nearly completed the act of separation; the final escape of the 
new individuals was not witnessed, nor has the species been 
identified. I feel confident that it is not A. meleagris. 
It cannot excite surprise that these cystic forms were for a 
long time mistaken for developmental stages of the stalked 
vorticellids with which they are found thus intimately con- 
nected. 
I note a third and very different infusorial cyst which in 
purpose may not be very far removed from the foregoing. It 
was found to occur in June on an alga from a swamp; it was 
small, globular, mounted on a short stem, nearly straight. Sur- 
rounding the globe were three prominent rings in the places of 
the equator and tropics of the earth. The finely granular, 
quiescent animal could be seen within the hyaline shell and an 
occasional pulse of the vacuole witnessed. It was regarded as 
a cyst of some one of the Tentaculifera and was compared with 
