56 Royal Society. 



mucous membrane in longitudinal folds, studded with minute fol- 

 licles and a rudimentary glandular appendage in the male. 



The efferent duct is constituted of the membranous portion of 

 the urethra. 



The seminiferous gland consists of the testicle, a collection of 

 convoluted tubercles, of an excretory duct called the vas deferens, 

 of a receptacle the analogue of the uterus, the vesiculre seminales 

 being the body, the prostate the glandular appendage surrounding 

 the cervix. The efferent duct is of considerable length ; the re- 

 ceptacle is lined with an alveolar fissure like the gall-bladder and 

 some muscular fibres. 



The ovuliferous organ consists of the ovarium or secretory ele- 

 ment, the fallopian tubes or excretory duct, the uterus or recep- 

 tacle, the cervix and its glandular appendage in the shape of mucous 

 follices, and tlie vagina or efferent duct. The secretory structure is 

 not tubular, but vesicular ; the excretory duct is connected with the 

 ovarium by its fimbriated extremity at certain periods only, in con- 

 formity with its peculiar function. 



The lactiferous gland is remarkable for the singular distribution 

 of its elements ; the secreting portion or breast, and the excretory 

 duct or nipple , being attached to one individual, and the receptacle 

 or mouth, cervix, glandular appendage or tonsils, and efferent duct 

 or oesophagus belonging to another, of which the mother and child 

 afford an illustration. 



The stomach or digestive gland does not appear at first sight to 

 be formed upon the same type as the other glands ; it is however 

 divisible into three distinct cavities — the secreting or cardiac, the 

 receptacular or pyloric, and the efferent or duodenum. It is a tube 

 of enormous calibre, divided into three compartments of unequal 

 area. The excretory tube is recognized in the central contraction 

 of the muscles during digestion ; the cervix, lined with plicated 

 mucous membrane, has been poetically described as the pylorus. 



Comparative anatomy as well as microscopical bear testimony to 

 the correctness of this view Mith regard to structure and develop- 

 ment. 



The biliferous gland is constituted as follows : 



The secreting element, popularly called the liver. 



The hepatic duct is the excretory tube. 



Tlie gall-bladder is the receptacle terminating in the duodenum 

 in conjunction with the pancreatic duct, the pancreas being the 

 glandular appendage surrounding the slender cervix of the recep- 

 tacle, and the duodenum performing the function of an efferent 

 canal to the digestive and biliferous glands. 



The glandular appendages are subject to great variety of deve- 

 lopment. The thyroid, the pancreas, and the }!rostate arc large 

 structures, whilst in the pylorus, the sigmoid flexure of the colon 

 and the cervix uteri, the same element is little more than a fold of 

 mucous membrane with follicles interspersed. This element, like the 

 glandular apparatus, is greatly predisposed to cancerous degeneration. 



