SYSTEMATIC SYNTHESIS OF TISSUES INTO ORGANS. 359 



FIG. 2C8. 



GLANDS is not known. 

 They are found singly, 

 and called solitary, or 

 in clusters, when they 

 are called agminated. 



Fig. 238, magnified riew 

 of Payer's gland, a, tubular 

 glands. /, depression of mem- 

 brane, owing to absence of 

 a : b, d, muscular tissue ; c, 

 sinewy tissue ; e, serous sur- 

 face. 



Remark. The second stomach and colon are also, oi' course, sup- 

 plied with mucous glands. 



Liver and Gall-Bladder. 



1094. THE LIVER is the largest gland in the body, 

 and, like all compound glands, is merely an aggregate 

 of minute parts, all of which are similar to each other, 

 and in the liver called lobules. 



1095. THE LOBULES OF THE LIVER CAN BE SEEN by 

 tearing it, when it will exhibit a fine granular struc- 

 ture, each granule being a lobule, and the whole bound 

 together by a small amount of sinewy fibres ; they are 

 interwoven with an immense number of blood-tubes and 

 some nerves, while the whole are enclosed by sinewy 

 tissue, finished with cells, forming a serous membrane. 



1096. EACH LOBULE is CONSTRUCTED of supplying 

 blood-vessels which encircle its surface, and a vein spring- 

 ing from its centres ; between the former and the latter 

 an exquisitely delicate network of capillaries exists, in the 

 meshes of which are the secretory cells of the lobules, 

 secreting the bile from the blood of the capillaries, and 

 pouring it into the bile-ducts between the lobules. 



1097. Remark. However curious it may seem, PHYSIOLOGISTS ARE 



Describe Fig. 238. 1094. What is ? 1095. How can ? 1096. Howls? 

 109T. In what are -? 



