ABSTRACT
By the use of histochemical techniques, the lipids (fatty acid, neutral fat, and phospholipid) were studied in the villi of the small intestine of the rat, 1 h and 2 ¾ h after feeding with oleic acid. The results of these experiments were identical with those previously described when triolein was administered. Neutral fat, fatty acid, and phospholipid were present in varying quantities within the cells. Between the cells and in their striated border, neutral fat and fatty acid were detectable. Within the cells, fatty acid was most abundant 1 h after feeding, whereas neutral fat and phospholipid predominated 
h later. The direct relationship between the amounts of neutral fat and phospholipid present in the cells, which had been observed in the studies with triolein, prevailed in the experiments described here.
