DESCRIPTIONS OF GENERA AND SPECIES 



669 



sperm-ducts and the glands, such as occurs in the allied genera Kynotus and 

 Callidrilus; or, rather we should say, without prejudicing the question as to the 

 homologies of the glands in question, that in Microchaeta the sperm-ducts open 

 directly on to the exterior, not through any glands whatsoever. 



Another matter in which the present genus resembles the majority of the 

 Old-World Geoscolicidae is in the form and position of the spermathecae. They 

 are invariably placed far back, in the neighbourhood of the testes and ovaries; 

 in M. rappi there are a number of minute oval pouches in segments xiii, xiv, xv, xvi ; 

 the average number appears to be three of these on each side, but there is considerable 

 variation. In M. papillata there are altogether ten or twelve pairs, on either side of 

 the body in segments xiii, xiv; in M. belli there are fewer — eight altogether — in 

 segments xii, xiii. 



The reduction in the number of the spermathecae has progressed still further in 

 M. heddardi; in this species there are only four altogether, two in each of segments 

 xii and xiii ^ ; finally, in M. benhami there are six pairs, one in each of segments 

 xi-xvi. 



The five species of the genus Microchaeta are, with the exception of M. benhaTni, 

 whose locality is unknown, African. Their principal characters are noted in the 

 accompanying table. 



(i) Microchaeta rappi, Beddakd. 



Lumbrious miorochaetus, Rapp, Jahresheft Ver. f. vaterl. Nat. Wiirtemberg, 1848, 



p. 14a. 

 M. rappi, Beddaed, Trans. Zool. Soc, vol. xii, 1886, p. 6^. 

 Antaeus microcliaetus, Vaillant, Anneles, p. 185. 



' See footnote to p. 672. 



