South HEN — Monograph of the British and Irish Oligochceta. 171 



Internal Structure. 



Having only a single specimen to dissect, I was unaljle to determine the 

 precise relations of the genital organs. This applies especially to the female 

 organs. There are 4 pairs of spermathecae present in segments 17-20. The 

 most astonishing fact was the presence of 3 pairs of testes and sperm-funnels 

 in segments 18, 19, and 20. They are large, glistening, and much folded. 

 There appeared to be 4 sperm-sacs in segments 17, 19, 20, and 21 (Text fig. 3) ; 



Spermathecae 



Sperm-sacs. 



Sperm-duct. 



Fig. 3. — Eeproductive organs of Selodrilus reliciua. 



but I was unable to determine their precise relations to each other, and the 

 figure given is only approximate in this respect. The last pair of sperm-sacs 

 was the largest, stretching through 2 segments. 



The female organs were not observed, but it seems likely that the small 

 pores on segments 24 and 25 were the openings of the oviducts, in which case 

 the female organs would also be abnormal in number and position. 



The presence of three pairs of testes and sperm-ducts is quite unique in 

 the Lumbricidse, the usual number being two pairs. Several species liave 

 been described, however, such as Octolasium hemiandrum (Cognetti), Octo- 

 lasium Damianii, Cognetti, &c., which have only a single pair of testes. In 

 Octolasium Damianii (7. p. 3), the opening of the male duct is on the 

 twenty- seventh segment. 



I have provisionally placed this species in the sub-genus AUolobophora, 

 as it has 4 pairs of sperm-sacs. Tlie backward position of the clitellum, 



