i] STRUCTURAL AND SYSTEMATIC 29 



structure, which is more reminiscent of the Geoscole- 

 cidae than of the Megascolecidae or Eudrilidae. In 

 this family there are no glands appended to, or in 

 the neighbourhood of, the orifices of the sperm ducts, 

 such as are found in the other forms. As in the 

 Geoscolecidae the clitellum is furnished with setae 

 somewhat different in form from those which deck 

 the body generally. These setae are never more than 

 eight in a segment. Dorsal pores (absent in Geosco- 

 lecidae and in Eudrilidae) are invariably present. 

 The spermathecae are without appendices and nearly 

 always simply paired, though rarely we get numerous 

 much smaller spermathecae in a single segment, as 

 in Kynotus among the Microchaetine Geoscolecids. 

 Internally the most striking feature of this family is 

 to be seen in the position of the gizzard at the end of 

 the oesophagus and at the beginning of intestine. The 

 apertures of the male pores are save for two or three 

 exceptions where they are further for ward invariably 

 upon the fifteenth segment, and the clitellum, often 

 very long, usually begins behind this point, features 

 which are also seen in Kynotus. 



Finally we have the Moniligastridae which differ 

 from all the types hitherto considered in a few rather 

 important particulars. These worms are named on 

 account of the fact that they possess several gizzards 

 upon the oesophagus, a character which is however 

 met with in the Megascolecid genus Plionogaster 



