Miscellaneous. 263 
and endowed with alternate movements of contraction and expan- 
sion. He has since succeeded in observing the contractions of the 
spot in the living animal. Notwithstanding the analogy which these 
phenomena present to those observed in the Infusoria and Rhizo- 
poda, their signification remained obscure until the acquisition of a 
better notion of the morphological condition of cells. Thus the 
movements of the germinal spot could not be assimilated to those 
of which the contractile vesicle of the animals just mentioned is the 
seat, as in the ovules and other cells of animals we were unacquainted 
with any canals comparable to those connected with the contractile 
vesicle of the Infusoria. These the author now professes to have 
discovered, from which he considers we are justified in assuming the 
existence of a true circulation in these elementary parts of the 
organism. 
The animal on the ovule of which the author’s observations were 
made is Geophilus longicornis. When the fresh ovary of this My- 
riopod is placed under the microscope, and the ovules are examined 
through its walls, an organ is detected which possesses more bril- 
liancy than the surrounding vitellus, and appears like a prolon- 
gation of the germinal vesicle. With slightly acidulated water this 
appears distinctly as an infundibuliform canal, more or less recurved, 
of which the wider orifice is continuous with the membrane of the 
vesicle, whilst the opposite extremity reaches the surface of the 
vitellus. Generally the canal seems to terminate suddenly at this 
point, opening by a circular orifice under the envelope of the ovule ; 
but sometimes it appears to be continued into a delicate prolonga- 
tion, emitting ramifications which spread more or less over the sur- 
face of the vitellus. In certain positions the axis of the canal is 
seen to be occupied by a much narrower interior canal, proceeding 
from the germinal spot and narrowing rapidly after penetrating 
into the outer canal. 
The germinal spot is occupied by a greater or less number of va- 
cuoles, capable of alternate contraction and expansion. At the 
moment of the extreme expansion of one of these vacuoles its walls 
appear to be directly continuous with those of the canal which ter- 
minates at the spot, the vacuole then looking like the enlarged am- 
pulliform end of the latter. When less dilated and seen in profile, it 
appears only to communicate with the canal by a narrow aperture 
like a pore. 
The width and apparent length of the two canals are in relation 
to the degree of development of the ovules; but they are to be seen 
in the youngest. In older ovules they continue visible as long as 
their transparency is not obscured by vitelline elements; and they 
probably persist as long as the germinal vesicle and spot. 
In seeking for similar structures in other ovules, the author ar- 
rived at the following results :—In the ovules of the Bitch the vesicle 
and spot each present a canal, as in Geophilus. In the Skate, the 
ovules of which usually contain from one to four small germinal cor- 
puscles with a central vacuole, each of these emits a variable number 
