DEVELOPMENT OF THE ALIMENTARY SYSTEM. 409 



an enormous size. According to Bischoff, 1 two projections, 

 or buds, appear on either side of the intestine, which form 

 the two principal lobes of the liver. This organ is at first 

 symmetrical, the two lobes being of nearly the same size, 

 with a median fissure. One of these prolongations from the 

 intestine becomes perforated, and forms the excretory duct, 

 of which the gall-bladder, with its duct, is an appendage. 

 During the early part of foetal life, the liver occupies the 

 greatest part of the abdominal cavity. According to Bur- 

 dach, its weight, in proportion to the weight of the body at 

 different ages, is as follows : At the end of the first month, 1 

 to 3 ; at term, 1 to 18 ; in. the adult, 1 to 36. a Its structure 

 is very soft during the first months, and it is only at about 

 the fourth or fifth month that it assumes one of its most im- 

 portant functions ; viz., the production of sugar. 3 As devel- 

 opment advances, and as the relative size of the liver gradu- 

 ally diminishes, its tissue becomes more solid. 



The pancreas appears at the left side of the duodenum, 

 by the formation of two ducts leading from the intestine, 

 which branch and develop glandular structure at their ex- 

 tremities. The spleen is developed, about the same time, at 

 the greater curvature of the stomach. This organ is abun- 

 dantly supplied with blood-vessels, but has no excretory duct. 

 According to Meckel, the spleen becomes distinct during the 

 second month. 4 



There is no reason to believe that any of the digestive 

 fluids are secreted during intra-uterine life. The stomach, at 

 least, never contains, at this time, an acid secretion. At 

 birth, the intestine contains a peculiar substance, called me- 

 conium, which will be described farther on. Cholesterine, 

 an important constituent of the bile, is found in the meco- 



1 BISCHOFF, Traite du developpement de Phomme et des mammiferes. Encyclo- 

 pedic anatomique, Paris, 1843, tome viii., p. 330. 



2 BURDACH, Traite de physiologic, Paris, 1838, tome iii., p. 483. 



3 BERNARD, Lecons sur la physiologic experimentale, Paris, 1855, p. 82. 



4 MECKEL, Manual of General, Descriptive, and Pathological Anatomy, Phila- 

 delphia, 1832, vol. iii., p. 321. 



