Smith — Lake Superior Lumbriculids. 39 



spermathecae paired in 12-15. This is the first record in the species of 

 three pairs of oviducal funnels, and this number was recorded but once 

 by Mrazek (1907:420) among 163 specimens of Lumbriculus variegatus. 

 The other specimen having spermathecae is from the other bottle and has 

 paired atria in 10; paired spermaries and spermiducal funnels in 9 and 10; 

 paired ovaries and oviducal funnels in 11 and 12; and paired spermathecae 

 in 11-13. 



The sperm ducts could be traced throughout most of their course in 

 each of the two mature specimens. As noted by Mrazek (1907:434) in 

 L. variegatus, the ducts are very slender, have a tortuous course, and are 

 followed with difficulty. There is almost certainly a general correspondence 

 in their course and in their relation to the atria, with the conditions found 

 in Trichodrilus. The course of the ducts of either side is: (a) along the 

 anterior surfaces of their septa, ventrad to the body wall; (b) along the 

 latter, with more or less tortuous windings, to the atrium; and then (c) 

 along its surface to the summit, where the lumen of each duct becomes 

 continuous with that of the atrium. Each duct from 9 extends dorsad 

 on the anterior side of the corresponding atrium and that from 10 on the 

 posterior side. 



The writer has recently received from Dr. Paul S. Welch, specimens 

 of L. inconstans which were collected in Douglas Lake, near Cheboygan, 

 Michigan, in July, 1918. One of these which is sexually mature has been 

 sectioned and it also exhibits the Trichodrilus relation of spermiducal 

 organs. 



In a discussion of the position of Lumbriculus in the family Lumbricu- 

 lidae, Michaelsen (1908:165-166) has mentioned the need for information 

 about the relations of sperm ducts and atria in L. inconstans. He also 

 suggested the possible desirability of uniting Trichodrilus with Lum- 

 briculus. He considered the various characters which separate the two 

 genera, as relatively unimportant. While admitting that any one of the 

 characters might by itself be insufficient to warrant generic separation 

 of the two groups of species, the writer considers that much more import- 

 ance should be attached to the existence of a considerable number of 

 such differences than to the presence of but one or two. An additional 

 difference, not mentioned by Michaelsen, is in the position of the sper- 

 mathecal pores. In L. variegatus and L. inconstans the pores are dorsad 

 of the ventral seta bundles and in or near the lateral line; while in Trichod- 

 rilus, they are posteriad of the ventral seta bundles and in line with them, 

 as in most lumbriculids. 



Literature Cited. 

 Eisen, G. 



1895. Pacific Coast Ohgochseta, I. Mem. California Acad. Sci., 2:63- 

 122. 

 Michaelsen, W. 



1901. Oligochaeten der Zoologischen Museen zu St. Petersburg und 

 Kiew. Bull. Acad. Imp. Sci. St. Petersburg (5), 15:137-215. 



