36 EARTHWORMS AND THEIR ALLIES [ch. 



also small worms, but show in some respects a higher 

 grade of organisation than their allies. While asexual 

 generation is general, the reproductive organs are 

 more commonly found than in Aeolosoma, though 

 there are still many hiatus in our knowledge of the 

 same in certain genera. Where they are known it 

 has been found that the spermaries and ovaries are 

 very far forward in the body, in the fifth and sixth 

 segments respectively. The spermathecae are in 

 segment six and the male ducts open into a terminal 

 chamber, called ' atrium,' which is on the whole not 

 unlike that of the Tubificidae. The blood in these 

 worms is red as in the higher types, and thus differs 

 from that of the genus Aeolosoma. The setae are 

 rather varied, being in some cases long and slender, 

 sometimes greatly exaggerated in length as in 

 Riplstes; other setae are forked at the free end, 

 and in Paranais this is the only kind of setae met 

 with. A marked feature of this family is that the 

 dorsal bundles of setae do not always begin like the 

 ventral setae upon the second segment of the body. 

 Indeed in Schmardaella there are no bundles of 

 dorsal setae at all. The Indian genus Branchiodrilus 

 is remarkable for the fact that it has paired processes 

 of the body which may be termed gills and which 

 in some segments involve the dorsal setae. Another 

 kind of gill is found in the genus Dero (which has 

 many species) and in the allied Atdophorus. These 



