£14 Illinois State Laboratory of Natural History. 



(d), on the anterior face of which the male pore is carried 

 and concealed by the slightly overhanging* margin. Thus is 

 formed, probably through the contraction of the dorso-ventral 

 muscles, a sort of genital sinus inclining dorsad and cephalad 

 deeply into the body and opening by a wide mouth on to the 

 surface of annuli XII « 2 and bo. 



The neighborhood of the female pore is reciprocally elevated 

 as a sugar-loaf shaped papilla, inclining caudad and ventrad 

 and consequently well adapted to occupy the male pit, in 

 which event the female pore ( 9 ), situated at its apex, 

 would come into contiguity with the male pore near the 

 bottom of the pit. 



The copulatory gland pores {cgp) are much more conspic- 

 uous than in the individuals first described, but are subject 

 to much variation. Typically they are arranged as follows : 

 In the male system {dcgp) a pair (concealed in the figure) is 

 placed symmetrically beside the male pore ; a second pair, 

 and sometimes an additional median one, is situated just in 

 front of the anterior border of the pit ; on the furrow 

 XII a 1\b 5, just external to the pit, is a third pair; a 

 fourth pair is found just abreast of the last but on the lateral 

 walls of the pit within its month ; and, finally, a median pore 

 appears on the sloping posterior face of the pit cephalad of 

 the third and fourth pairs. 



An almost exact reversed counterpart of the male system 

 is found in the female system of adhesive organs ( 9 cgp). It 

 is described in the order in which the pores are supposed to 

 correspond with those of the male system as respectively 

 enumerated. The first pair occupies the sides of the female 

 papilla close to the genital orifice ; the second is found on 

 annulus XIII b2, caudad and laterad of the papilla and 

 sometimes accompanied by a median one ; the third and 

 fourth pairs of the male system are represented by a 

 single pair in the female system, which is just caudad of the 

 male pit on annulus XII b 6. A median pore situated just pos- 

 terior to these completes the parallelism. 



*The ventral surface being turned uppermost. 



