544 * H. p. KJBKSCHOW AGER8B0RG 



fibrous coat with a few occasional muscle-fibres (Cc). This 

 same cover, in the pyloric diverticulum, is very loose (PI. 33, 

 fig. 44, Vas), and suggests a possibility of interchange of body- 

 intestinal fluids in this part of the alimentary canal. The outer 

 coat of the remainder of the intestine, though much thicker, 

 is, however, so loose that it may allow ready interchange of 

 intra- and extra-intestinal fluids. 



There are then, five distinct regions of the alimentary 

 canal each differing from the other in structure and function. 

 These are (1) the oesophagus with the non-glandular lining 

 below which are the oesophageal or salivary glands (PI. 33, 

 figs. 36, Oe, 41, Sg) ; (2) the proventriculus with distinct 

 glandular lining (PI. 33, figs. 36, G, 38, Gl) ; (3) the gizzard 

 with its stomach-plates (PI. 33, figs. 37, 42-3, StpJ) : (4) the 

 pyloric diverticulum with its glandular and ciliated internal 

 surface, which secretions, as in the glandular stomach, do not 

 keratinize (PI. 33, figs. 38, 39, 44) ; (5) the intestine with its 

 large typhlosole and glandular ciliated epithelial surface 

 (PI. 33, figs. 40, 45, PL 34 figs. 56, 57). 



(5) The Liver. 



The gastro-hepatic apparatus, or hepatic caeca of M. 

 1 e o n i n a , does not arise as in M . f i m b r i a t a , "... a little 

 in advance of the belt of horny processes ' (Alder and Hancock, 

 1864), but it arises from the anterior portion of the gizzard 

 and consists of a very extensive arborization which passes to 

 all parts of the body (figs. 1, 2, Hp, 7, 9, He, 40, Hep). 

 As in other members of this genus, the liver consists of three 

 principal tubular trunks which start at the anterior end of the 

 gizzard and pass to the various parts of the body. Two of 

 these trunks, situated opposite each other, send out branches 

 as follows : the one on the left side runs in the main to the 

 gonads, branching very profusely in that region ; it also sends 

 out other but minor branches, some to the papillae, some to the 

 body-wall, and one to the mucous gland. (The mucous gland 

 = (1) albuminous gland, and (2) nidamental gland.) The right 

 trunk sends out several major and minor branches. Of the 



