328 PROCEEDINGS OF THE ACADEMY OF [^^^ay, 



good results. As might be expected from the habits of land 

 isopods, not all of the fat taken from a pure diet of this kind in 

 the course of ten minutes' continuous feeding is absorbed. Pellets 

 of waste containing a large proportion of fat were found forty-eight 

 and seventy-five hours after feeding. But enough of the fat is 

 absorbed, as may be seen from the figures, both to demonstrate the 

 fat-digesi ing power of the hepatopancreas ferment and to follow the 

 fat tlirough the absorbing cells. Animals live indefinitely after 

 eating the above-mentioned foods, and liave been seen to eat the 

 same repeatedly. 



The digestion of pure fat, like that of pure proteids, is rather slow 

 as compared with the action in mammals. At eight hours after 

 feeding fatty globules may be seen in the epithelium of fresh intes- 

 tines without the agency of stains. Fig. 15 shows an anterior intes- 



'..•®; 



Fig. IG. — Section involvino- parts of two cells X GOO from intermediate 

 portion, "mid-gut" oi Porccllio spmicornis, fed witli butter: intestine 

 lixed after 12 lirs. as in fig. 15. All black granules outside the nucleus 

 are fat. Int., intima ; Pal, palisade. 



tinal cell from an animal fed with butter for fifteen minutes, the 

 intestine fixed after eight hours in Hermann's fluid Avithout acetic 

 acid. The sections were stained in iron-hsematoxyliu. The 

 size of the globules varies greatly, the larger ones being doubt- 

 less due to the fusion of several small ones. It will be seen also 

 that no large globules are found near the free luminal edge of the 

 cell, but that in general there is an increase in size Avith tlie distance 

 from this edge. Tliis is typical of the appearance presented by all 

 absorbing cells at an early stage in the absorption. Later, as is 

 shown in fig. Ifi (12 hrs. ), there is not so much difference in size. 



