Digestive Processes in Arachnids. By II. M. Bernard. 439 
very marked and regular in the cephalothorax, but as a confused mass 
in the abdomen ; in both cases they were black or mottled. Sections 
show that this black colour is due to accumulations of the minute 
crystal-like bodies with which we are now familiar, but which must, 
in this case, he due to the reduction of yolk, as the animals had 
certainly not taken in any extraneous food. This is very suggestive 
when taken in connection with the great resemblance under the 
Microscope between the food-globules and yolk-granules. The fact 
that the digestion of the yolk-granules in these Arachnids leaves as a 
residue the typical faecal “ crystals ” of ordinary enteric (intracellular) 
digestion of food-globules, may throw some light upon the nature of 
the yolk. May it not be possible that the yolk is in this case un- 
assimilated food, such as in Euscorpio passes out of the digesting cells 
to form the stored up food-globules in the peritoneal cells, and in 
Tubifex probably forms the brown bodies on the walls of the dorsal 
blood-vessels, which bodies are taken up, and apparently assimilated, 
by the chloragogen cells ? It would be interesting to know whether 
these faecal “ crystals ” always result from the assimilation of yolk. 
Galeodim. 
The Galeodidae agree with the Araneids in having no long hind- 
gut such as we find in the Chernetidae and the Scorpionidae. The 
diverticula open into a central canal, which again opens into a hind- 
gut specialized into a stercoral pocket. As in Scorpio, the digesting 
cells are of all shapes, according to the space they have for their 
development. That there is no specialization of the epithelium lining 
the diverticula in Galeodes has lately been pointed out by Birula,* 
who shows that the cells throughout the whole intestinal canal are of 
essentially the same character. They are sometimes long, and 
almost thread-like, preserving, however, their character throughout. 
The peritoneal cells are very unevenly developed, sometimes quite 
undemonstrable. 
One specimen examined ( Galeodes grsecus , kindly sent me by 
Prof. Mobius) had been killed immediately after a good meal; its 
abdomen was so swelled up that I had taken it for a pregnant 
female. The abdominal diverticula and even the central canal were 
surcharged with coagulum, and a wonderful confusion reigned. 
The epithelium was completely disorganized, and the tubes were 
distended by an amorphous mass of coagulum, food- globules, faecal 
“crystals,” and here and there moth’s scales, or feathers (fig. 6). 
I was quite prepared for the breaking off of the distal ends of the 
digesting cells when overloaded with food-globules, but the complete 
disintegration of the whole epithelium I did not expect, and could 
hardly believe, in spite of my inability, after prolonged searching, 
* “ Der Mitteldarm der Galeodiden,” Biol. Centralbl., xi. p. 295. 
