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Transactions of the Society . 
Galeodidse. As might he expected in such an unworked field, many 
points have come to light not only new in themselves, but affording 
new interpretations of facts well known but incompletely understood. 
For the sake of clearness, I shall keep the observations on each 
group distinct. 
The Chernetid^. 
I take these first because, as will be seen from what follows, they 
are in many respects the least specialized. The specimens examined 
were Obisium museorum and 0. cancroides, kindly given me by 
Dr. Gunther, F.B.S. 
The digesting cell of Obisium is a large lobate body, so filled with 
food-globules that the nucleus is quite obscured (fig. 1). I have not 
been able to follow the conversion of the food, which in the sections 
looks like a granulated coagulum lying in the lumen of the gut, into 
the clear, homogeneous food-globules within the cells. 
The importance of commencing with the Chernetidae lies in the 
fact that the homogeneous spherules in the mid-gut cells of these 
animals are at once recognizable as food-globules, and not as the 
secretions of gland-cells. In the Araneids, on the other hand, this 
point is not so evident. The long, thin tubules branching from the 
gut in these latter animals are more like glands than digesting 
diverticula, and they have almost universally been considered as 
such. There was, therefore, every excuse for those who examined 
these gland-like diverticula when they imagined that the contents of 
the cells were secretions which were to be poured into the gut for the 
digestion of the food. It is true that Bertkau found that food 
sucked in found its way to the tips of these diverticula, but that 
fact alone was hardly sufficient to lead him to recognize the refrac- 
tive globules in the cells as ingested food. Had he begun with any 
of the Chernetidae, as I was fortunate enough to do, he would at 
once have recognized this fact, because in these Arachnids it is quite 
impossible to mistake the mid-gut diverticula for glands of any kind ; 
they are simple distensions, often very shallow, of the digestive tube. 
While, therefore, the observations of Plateau * and Bertkau t 
dropped out of some of the vacuoles in the process of section-cutting. The protoplasm 
of the cell is much vacuolated. A tracheal tube runs through the peritoneal cells. 
Fig. 8. — A group of vacuolated digesting cells of Ehax, there being no food- 
globules in the vacuoles. The whole digestive system is empty, excepting that here 
and there groups of faecal “crystals” occur, the remains of a previous meal, which 
have failed to tind their way out into the central canal. 
* “ Eecherches sur la structure de l’appareil digestif et sur les phenomenes de la 
digestion chez les Araneides dipneumones.’ In three parts. Bull. Ac. R. Bruxelles, 
xliv. (1877). 
f “Uber den Bau u. die Function der sog. Leber bei den Spinnen,” Arch. f. 
Mikr. Anat., xxiii. (1884). 
