678 



ZOOLOGY 



SECT. 



From the buccal cavity runs backwards a long narrow tube 

 with sacculated walls the ccsophagus (Figs. 576 and 578, ccs.\ 



Posteriorly this opens into 

 a large ovoid sac the crop 

 (Fig. 576, crop}. The outer 



rad- 



FIG. 577. Triton nodiferus. Interior of the 

 buccal mass, from above, magnified. I. jaw, left 

 jaw ; odoiit. lateral surface of odontophore ; rad. 

 radula ; r. jaw. right jaw. 



pears marked with numer- 

 ous close-set fine lines, 

 transverse or 

 direction, andj 

 cavity of thai 

 opened, it is jhl 

 these correspond^ 

 ous delicate foil 

 extend to near the middle, 

 and almost completely 

 block up the lumen. On 

 either side of the crop is 

 a large gland the salivary 

 gland (Fig. 576, /. sal, a/., 

 Fig. 580, r. sal. gl.) partly 

 composed of a compact glandular substance, partly of spongy 

 tissue in which the secretion collects. The two salivary glands 

 are unlike in size and shape, that on the left-hand side being 

 much longer than that on the right. Each has a narrow duct 

 (sal. die.) which runs forwards and inwards to the dorsal aspect 

 the oesophagus, 

 where the two 

 come into close 

 apposition, be- 

 coming embed- 

 ded in the wall 

 of the oesopha- 

 gus, along which 

 they run for- 

 wards to open 

 into the buccal 

 cavity. 



From the crop 

 leads backwards 



anrl +n tViA laff Fl - 578 Triton nodiferus. Diagrammatic longitudinal vei 

 tical section of buccal cavity; bod.- car. body cavity; cart, ca 

 a narrow Cylin- tilage of odontophore ; jcur, right jaw ; as. oesophagus ; ra 



drical tube the 



boci. casts 



CCLT't 



radula ; /<,</. sac. radula sac. 



posterior ces<>- 



phagus. On this follows a stomach (Fig. 574,som.) which is in th< 

 form of a U-shaped tube partly embedded in the substance < 

 the liver, the hepatic ducts from which open into it. The tubuh 



