around the pharynx numerous round or jicar-shaped glandular cells are found, with round nuclei 

 and finely granular cytoplasma. These are probably the cells of the "vordere Bauchdrlise", but 

 this cannot be determined with certainty. 



The structure of the alimentary canal in the anterior part of the body furnishes the 

 trreatest peculiarities. Fig. 150 gives a reconstruction; the schematic sections figs. 151 — 157 

 correspond to the lines AB — NO. The mouth-cavity is large, but pardy filled with the fold/ 

 of the dorsal wall. A great number of ramified cirrhi are present; "Mundleisten" are absent. 

 Distally from the fold /", the mouth-epithelium is strongly folded and ciliated. The mouth-cavity 

 leads into the pharyn.x, similarly ])rovided with a folded ciliated wall in the anterior region; 

 more distally the shape of the pharynx becomes more round or irregularly oval-shaped (fig. 152). 

 More distally it widens considerably. 



2 Salivary glands merge into the ])harynx ; they are globular organs {{^cr. 153 sg.), 

 consisting of long granular glandular cells with rounil nuclei. A lumen is wanting, but between 

 the glandular cells small openings and slits occur, enabling the secretion to flow into the 

 pharynx. In fig. 154 it is seen that the pharyn.x is going to divide into a large ventral part 

 and a smaller dorsal one; the latter is separated from the first and leads into the intestine 

 after having united itself with the proximal coecum (fig. 155). This coecum is large, with 

 strongly folded wall, more proximally divided into different parts (fig. 153). The pharyn.x is for 

 some length continued into the intestine as a deep fold, the folds / closing ventrally from the 

 pharyn.x (figs. 155 and 156). 



Very remarkable are the radula and the radula-sac. Figs. 154 — 156 show the folded 

 wall of a in the lumen of the pharynx 0. More distally in fig. 156 it is seen that th(> dorsal 

 walls of a and d unite; in i\'i^. 157 it becomes clear that a is an invagination of d. Thus the 

 distal and dorsal wall of the ventral portion /> of the pharynx is invaginated. The wall of d is 

 built up of cubical e])ithelium (fig. 15S). The structure of tz is different; fig. 158 shows that the 

 wall is peculiarly folded ; the dorsal folded wall partly consists of cubical, partly of cylindrical 

 epithelium with oval nuclei and strongly fibrillar cytoplasma. It is by these walls that the radula 

 is formed. The latter is an e.xclusively cuticular formation : a basal membrane with some teeth, 

 attached to the radula-sac in crypts. The teeth are more intensely stained with carmine than 

 the basal membrane itself, but undoubtedly the basal membrane and teeth form together one 

 mass. More proximall},- the walls of a and 6 approach and are lying side b)- side ; the radula 

 therefore being surrounded by epithelium on either side. Now the radula loses its connection 

 with a and attaches itself to />, the teeth thus coming free. From there the radula is pushed 

 along the pharyngeal wall in a dorsal direction. The radula is very strongly developed. .Along 

 both the lateral pharyngeal walls to a place close before the mouth-ca\ity the two broad 

 radula-bands are found. Fig. 159 shows a section through the pharynx; the wall is composed 

 of cubical epithelium, becoming higher more dor.sally {a) and presenting more or less vesicular 

 cells. The lateral walls are completely covered with the radula, which is flat with a few teeth. 

 A similarly large radula has not yet been observed for Solenogastres. In fig. 150 the contour 

 of the radula is indicated by a red line; in the pharynx the radula is 0.7 mm. long; the length 

 of the portion in the radula-sac is 0.3 mm.; the entire length of the radula is therefore i mm.. 



