Miscellaneous. 369 
connexion with the wall, they at last attach themselves to it by 
virtue of centrifugal development, and finally unite with it by their 
peripheral extremity, while by the opposite extremity they con- 
verge towards the centre of the cyst. They are formed by a struc- 
tureless membrane, and originate in the midst, and doubtless also at 
the expense of an accumulation of granules which surround them for 
some time even after their complete formation, representing a sort 
of muff round each of them. 
Each of these tubes, which I have called sporoducts, presents, in 
a state of complete individualization, a short, broad basal joint, by 
which it is inserted upon the internal surface of the wall of the 
cyst, and a slender terminal longer or shorter joint, of which the 
extremity corresponds to the centre of the cyst. 
At maturity the sporoducts may be seen to disengage themselves 
with extreme rapidity, and to erect themselves outwards to their 
full length. In case any obstacle obstructs the phenomena of their 
erection, we may easily trace its mechanism. We may then see the 
sporoduct free itself gradually by a true evagination, the basal joint 
appearing first of all, and the extremity of the tube last, after 
having traversed all the portion already emitted. This mechanism 
can only be the effect of an augmentation of pressure of the contents 
of the cyst, doubtless correlative to a change of its mean density 
under the influence of the remarkable modifications that these con- 
tents undergo in the course of sporulation; and the same cause 
would also direct the expulsion of the spores through the sporoducts. 
The genus Stylorhynchus (S. oblongatus, Hamm., from Opatrum 
sabulosum) presents perhaps yet more interesting phenomena. The 
cyst, which is produced by solitary encystment, presents at first uni- 
form contents, which are afterwards divided into two equal masses 
by an equatorial plane. At the same time that the traces of this 
first division are effaced and the granular portion of the contents 
becomes condensed, a great number of very shallow secondary fur- 
rows appear, which subdivide the outer coat of the granular contents 
into lobes and lobules.. From the surface of these lobes and lobules 
one now sees the nascent spores bud. At first they are completely 
homogeneous and transparent, but afterwards acquire some granules 
before their complete individualization and separation from the 
lobules. 
When free from all adherence to these, the sporigenous masses 
are situated on the surface of a voluminous central mass formed by 
the remains of the not utilized portion of the original contents. 
Then, quitting the regularly spherical form, each sporigenous mass 
elongates in the direction of a radius of the cyst, and all together, in 
the form of little fusiform bacilli, tapering at the ends and relatively 
very much swollen in the middle, execute, during from fifteen to 
eighteen hours, an interrupted series of rapid and energetic move- 
ments, by which their peripheral extremity inflects itself first in one 
direction and then in another, at the same time that the corpuscle 
shortens and lengthens itself, and the granules which it encloses are 
agitated in its interior in all directions. The movement of each 
corpuscle is independent of that of its neighbour; and those which 
