88 WARFARE IN THE HUMAN BODY 



the mesentery, and the changes undergone during its 

 development. It has often been pointed out that the 

 embryonic processes by which it is made secure are 

 histologically those of plastic organized exudations, i.e. 

 those which have been invaded by fibroblasts. These 

 attachments do not come about at the same period of 

 fcetal development, and it seems of significance when we 

 note that the mesentery of the small gut has an oblique 

 attachment, to the posterior abdominal wall from the 

 duodenum to the right iliac fossa, only found in animals 

 which have assumed the upright posture. This comes 

 into existence as late as the fourth or fifth month of 

 fcetal development. Before this band formed there must 

 have been a great series of disasters, for even now the 

 last part of the mesentery to become attached to the 

 abdominal wall, that is, the angle between the ileum 

 and ascending colon, sometimes remains free. A volvulus 

 may easily form there by rotation of the ileo-colic 

 loop. The whole history suggests a series of lymph 

 effusions, caused by pathological states, some of which 

 were sorted out by the lethal process of natural selection, 

 the remainder surviving and leaving offspring with the 

 liability to organize the effusion in the safe way. The 

 pathology of those cases, in which what are known as Lane's 

 Kinks can be found, is obviously of a similar character. 

 The stasis of the affected bowel causes lymph effusion, and 

 the formation of bands which are morphologically homo- 

 logous with the early attachment of the mesentery. In 

 Keith's paper, "Nature of Peritoneal Adhesions," I find 

 noted the normal loose network of connective-tissue bands 

 between the elephant's lung and the pleura. This is a 

 physiological development of evolutionary adhesions, and 

 clearly supports the pathological development of many 



