QUARTERLY CHRONICLE. 4 
to be as thick at the line of junction as elsewhere, and the 
long striations as perceptible. Here and there a Gregarina 
is to be found still moving iése/f, but enclosed by a structure- 
less, enveloping, elastic “ veil,” which resembles a cyst-mem- 
brane. The Gregarina, frequently swollen in the middle, 
is so placed that the finer ends are bent towards the thick- 
ened wall, so that they touch, the one under the other. The 
body-contents are alternately driven from the middle into the 
turned-up ends, and back again; or into one of the ends, 
when the walls of the hollow sac fall together, and part again 
so soon as the granules and fluid return. If the enveloping 
“veil” burst, the Gregarina stretches itself out straight again. 
The appearance of Gregarine within cells has been observed 
tooccur. They are often found in the vesicular corpuscles of 
the testicular sacs of the earthworm, when the spermatic 
filaments, in various stages of development, are disposed 
around their outer envelope. Such a Gregarina is sometimes 
so small as not to equal in size the third part of the diameter 
of the filamentous vesicle, in other cases so large that it quite 
fills up the vesicle, and in others it is still wider. These 
must not be confounded with the cyst-membranes, in which 
also the Gregariné sometimes show movements. By the 
movements of a large round Gregarina in water the hyaline 
cortical layer may be seen to thicken itself at particular spots, 
and thereby the upper layer to sink in. If the thickening 
extends itself upon the whole Gregarina annularly, it appears 
more or less laced in; the thickenings may also appear in 
more spots at the same time, and the resulting depressions 
- give the Gregarina the appearance of an Ameeba with short 
pseudopodia. In smaller examples this alternate thickening 
and thinning does not occur, since the cortical layer is too 
thin to permit of the separation appearing. It has been 
as yet universally admitted that the Gregarine become sur- 
rounded by a cyst, when the formation of pseudo-navicule or 
psorosperms takes place. As a rule, this is the case; and 
the published researches of Kolliker, Stein, and others thereon 
have received confirmation and assent. The formation of 
pseudo-navicels, however, takes place without encystation, as 
is evidenced by the minute groups of pseudo-navicules to be 
found in the testes of worms unencysted, yet held together 
by some glutinous substance. 
The remaining papers do not deal with microscopical mat- 
ters, excepting a very short one by Dr. Anton Schneider, 
“ On the Hematozoa of the Dog.” 
Archiv fur Naturgeschichte (Leuckart und Troshel), Third 
Part, 1865.—There are the following papers in this journal 
