214 Dr. W. E. Collinge on the 
of which converge towards the central part of the gland, 
giving this last the aspect of a little rosette. Each of the 
composing vesicles is finely granulated, an appearance which 
without doubt is due to the epithelium covering it internally ; 
their diameter varies greatly, the largest measuring at their 
base "75 mm. Several times I have seen a rather fine tube 
become detached from the glandular mass; this tube is, 
without doubt, an excretory canal; but I am ignorant as to 
how these very fine canals behave in the interior of the 
appendage. In the middle of each gland one or two opaque 
bodies can be seen, which have the appearance of granular 
nuclei. These bodies, ordinarily double or triple, are, I 
believe, rudimeutary vesicles, which will subsequently develop 
and will become similar to the other vesicles. This, I think, 
must be their rdle there, since one almost always sees 
around them transparent but much smaller vesicles than the 
others. 
‘“‘T have verified the existence of these glandular bodies 
in the genera of woodlice Porcellio and Armadillidium. 
No doubt but that they are the seat of the viscous secre- 
tion produced by these animals, for they themselves are 
very viscous, and their adherence to the needles or to the 
neighbouring parts, is one of the difficulties of their 
preparation. 
“The presence of these excretory organs is an interesting 
fact with regard to the bearing of zoological affinites. One 
knows that the silk of spiders is due to numerous vesicles 
contained in the abdomen: the matter secreted by these 
vesicles issues by the spinnerets aud presents scarcely 
any greater consistency at the moment of issue than the 
flowing matter of the woodlice, But in the spider the 
viscous substance coming out by the numerous holes of 
the sieve which terminates each spinueret, finishes by 
forming a rough tough thread, while in the woodlice, this 
matter issues by a single orifice.” 
Lereboullet’s description is very imperfect. His reference 
to the number of the glands as being four to six probably 
refers to the number of groups. He evidently observed the 
three nuclei, but was wrong in supposing that each would 
become a separate vesicle, and that the glands were com- 
pound. Further, the entire absence of any reference to these 
glands in the mesosome would seem to indicate that he 
observed them only in the metasome. 
Max Weber (9) in 1881 published his researches on the 
Trichoniscide, in which memoir he points out that in 
addition to the occurrence of these glands, which he rightly 
