MR. H. M. BERNAE^' ON THE CHERNETID^. 415 



A short distau'ce after the divergence of these three diverticula 

 the main trunk of the canal suddenly narrows to form what may, 

 perbaps, be the hind-gut. This forms a loop, running backward 

 to nearly the end of the body, bending forward again and then 

 backward. Just before the anal aperture, it widens to form a 

 kind of stercoral pocket, which is, however, by no means so 

 specialized as are the homologous structures in Galeodes and the 

 Araneids. The anus is apparently a transverse slit, but in 

 reality it is a median slit hidden in a transverse fold in the 

 cuticle. 



The epithelium of this intestinal tract shows but slight differ- ' 

 entiations. Erom the proximal end of the oesophagus to the 

 commencement of the " hind-gut," the cells are absolutely alike ; 

 there is apparently no division of labour ; each cell performs 

 all the functions of digestion, like an independent unicellular 

 organism. In Ohisium the cells are large and lobate, stretching 

 out far into the lumen. The food absorbed by them is transformed 

 into homogeneous globules which look exactly like oil-drops. 

 These are so numerous that the nucleus is completely obscured. 

 There is occasionally a peripheral layer of granular protoplasm, 

 traces of which may also be found between the food-globules. 



On close examination these food-globules are found to become 

 granular, and ultimately to break down into a number of minute 

 crystal-like bodies. These latter are regularly excreted between 

 the cells and cast out in a stream, apparently in some slimy sub- 

 stance, into the lumen of the gut, to mix freely with the undi- 

 gested food. "Where the alimentary canal suddenly narrows 

 to form the hi]id-gut, these " crystals " are separated from the 

 food, and from this point they alone are to be found, which 

 accounts for Menge's statement that faecal formation commences 

 at this point, whereas, as a matter of fact, it is at this point that 

 the faecal matter is separated from the other contents of the 

 canal. 



I have not hesitated to call these crystalline bodies faecal, as it 

 seemed clear to me that they were the undigested remains of the 

 food-globules in the individual cells ; they are found, apparently 

 unchanged, as by far the most important if not the only consti- 

 tuent of the faecal masses in the stercoral pocket. There can 

 therefore be very little doubt that they are the irreducible re- 

 mains of ingested food. 



While examining these small refractive granules I was 



