CHINESE EARTHWORMS GATES 491 



On the median wall of the invagination there is a lobulated ridge, 

 which bears 2-6 setae. The minute male pore is on a smooth glisten- 

 ing porophore in the dorsalmost portion of the invagination. The 

 shape of the porophore varies. In a majority of the specimens the 

 porophore is an elongated, lateromesially compressed ridge, the 

 ventral surface sloping dorsally toward the anterior and posterior 

 ends. The portion of the ridge on which the male pore is located 

 may be protuberant as a tiny knob. The porophores are shortened 

 anteroposteriorly in one specimen, diagonally placed in another, al- 

 most transverse in another. In another specimen the porophores are 

 shortened and more protuberant, rather conical, and somewhat penis- 

 like in appearance. The genital markings on the median wall of the 

 invagination are variable as to size, number, and location : 



I. One small, transversely oval, protuberant, presetal disk ; the 

 central portion grayish and translucent; the margin opaque 

 and whitish. 5 specimens. 

 II. Two oval disks, one presetal and one postsetal. 1 specimen. 



III. As in I but the disk hypertrophied, about 6 intersetal intervals 



wide transversely ; the median ridge dislocated posteriorly, 

 crowded against the posterior wall and apparently without 

 setae. 3 specimens. 



IV. A transversely oval presetal disk as in I and in additional one 



or more circular markings as in V. 

 V. Genital markings tiny, circular in outline, usually protu- 

 berant. Two presetal markings, 1 specimen. Two presetal 

 and two postsetal markings, 2 specimens (on one of these 

 specimens the latter markings unusually deep in the invagi- 

 nation and in contact with the male porophore). One 

 presetal and one postsetal marking, 1 specimen. 



The apertures of the male pore invaginations of specimens D gape 

 open widely. On the median wall of the invagination is a large, 

 presetal, transversely oval genital marking that is 4-5 intersetal in- 

 tervals wide transversely. In the clitellate specimens this marking 

 has grown posteriorly through the region on which the ridge should 

 be located. Setae appear to be lacking in the invaginations of the 

 clitellate specimens. The male porophore is in the dorsalmost portion 

 of the invagination and varies from a shortly conical penislike 

 tubercle with a bluntly rounded ventral end to an elongate laterome- 

 sially compressed ridge. On the median wall of the invagination 

 between the oval tubercle and the male porophore there is, in each 

 of the specimens, a smooth, glistening, tripartite, butterfly-shaped 

 area. The middle portion representing the body is slightly more 

 protuberant than the presetal or postsetal portions that represent 

 the spread wings. On the aclitellate specimen the male porophores, 

 the butterfly-shaped areas, and the oval disks are delimited, but 

 the parietal invagination is represented only by a slight crescentic 



