H. Friend 203 



lies in the coelom in near proximity to the nerve cord. It pushes back 

 the septum between the fourth and fifth segments, but does not normally 

 pass into the latter segment with the rest of the organ. Tubules are 

 given off at intervals, and the posterior extremity is branch ed. 



The dorsal salivary gland commences in front of the first septal gland 

 (Plate XXXII, d.s.g.) and lies between that body and the oesophagus. 

 It then passes posteriorly along the coelom attached dorsally to the 

 oesophagus, and ends in two or more small branches (Plate XXXII, b.s.g.) 

 in the 6th and 7th segments. Though both salivary glands lie in such 

 close proximity to the oesophagus neither has been observed to enter 

 into it. The condition described above is very similar to that which 

 Welch has so clearly set forth in his account of Henlea moderata. So 

 far as I am aware these two species, together with H. urbanensis, are 

 the only ones in which salivary glands of this type have yet been 

 described. The peptonephridia are certainly very valuable for purposes 

 of diagnosis on account of their great variation in shape, size and 

 position, and will in future play a more important part in both generic 

 and specific description. It should not be overlooked that in this 

 species, nephridia are found in the segments (6 and 7) which contain 

 peptonephridia. (See Beddard i. 47.) 



The oesophagus, whose lumen is ciliated, gives rise in segment 8 to 

 a pair of organs known as oesophageal glands or intestinal diverticula 

 (Darmtaschen). These are the chief distinguishing features of the genus, 

 and merit more than a passing study (Plate XXX, oes.g.). They are 

 attached to the oesophagus and open directly into it at the point where 

 the latter enters the intestine. They are somewhat heart-shaped, and 

 consist of a number of tubules, arranged irregularly round a central 

 cavity or duct (Plate XXVIII, cav.). In Henlea as above defined they 

 are always present, but vary in number and position. In H. moderata 

 Welch there is only one gland, which tends to relate it to Buchholzia, 

 while in H. ventriculosa there are four. Usually, however, there are 

 two, and these lie between the 7th and 9th segments. The latest 

 account of these structures is by Welch (8) who complains that most 

 descriptions are very meagre. It may be useful, therefore, if we give 

 some further details of their structure in H. fragilis. The glands, 

 though originating in segment 8, are not strictly limited thereto, nearly 

 one- fourth of the organ projecting through the septum into the posterior 

 portion of segment 7. The anterior extremity is more pointed at the 

 front than the section first chosen for illustration (Plate XXX) suggests. 

 The interior tubules are made up entirely of one form of cell, and the 



