MUCOUS MEMBRANE OF THE SMALL INTESTINE. 



317 



ening the villus, and this has actually been observed in speci- 

 mens taken from the intestine shortly after death. 



Fig. 2. 



The anatomy of the lac- 

 teals as they originate in the 

 villi has been the subject of 

 much controversy ; but almost 

 all anatomists are now agreed 

 that these vessels commence 

 either by a plexus or by blind 

 extremities, and have no di- 

 rect openings into the intesti- 

 nal cavity. The most gener- 

 ally received view at the pres- 

 ent day is that the lacteals 

 originate by a single delicate, 

 nearly straight vessel in each 

 villus; and that this vessel 

 has no ramifications in the 

 villus itself, but commences 

 by a single, rather dilated, 

 blind extremity near the 

 apex. 



Owing to the excessive te- been partially withdrawn by contrac- 

 nuity of the Walls of the lac- tion from its investing epithelium, 



the villi if indeed 



Intestinal villi, as seen by transmit- 

 ted light. The villus, marked 1, has 



which is thus left entire like the finger 

 of a glove. 



a, epithelium of the villus ; 6, gran- 

 ular matrix, or substances of the same. 

 (BRINTOX, Cyclopaedia of Anatomy and 

 Physiology, London, 1859, vol. v., sup- 

 plement, p. 354.) 



teals in 



they exist at all it has been 

 found impossible to fill them 

 with an artificial injection, 

 though the lymphatics sub- 

 jacent to them may be easily 

 distended and studied in this way. Those who profess to have 

 seen the single lacteal in the villus have done so by examining 

 the parts when the lacteal system has been engorged with 

 chyle. It seems, however, from a careful review of the whole 

 subject, that the view entertained by Sappey is most nearly 



