NEW SPECIES OF FLATWORMS — HYMAN 433 



widening into a sac very near the wall of the genital atrium. This 

 diverticulum is called uterus by some authors, seminal receptacle by 

 others ; it is probably actually a copulatory bursa. In R. terrestris it 

 gives off a pair of genito-intestinal ducts connecting with the adja- 

 cent intestine, one on each side. These ducts were seen in the present 

 specimen but owing to the damage to the sections could not be traced 

 into the intestine. Glandular duct and seminal receptacle are lined 

 by a tall epithelium probably ciliated. 



Color. — Jet black, uniform. 



Locality. — In rotten w^ood in woods near Oconomowoc, Wis.; col- 

 lected in July 1927, by Calm. 



Remarlifi. — This is the third land planarian, all species of Rhyn- 

 chodemus., to be found in the United States, The other two, R. 

 s-ylvaticu-s (Leidy, 1851) and R. atrocyaneus Walton, 1912, are pre- 

 sumably endemic, although so imperfectly known that it is difficult 

 to draw conclusions about them. A study of serial sections of the 

 copulatory apparatus is badly needed. At first the present specimen 

 was thought to be a new species, but study of the copulatory appa- 

 ratus revealed no good grounds for separating it from R. terrestris. 

 The best figure of the copulatory apparatus of European specimens 

 is that of Bendl (1908). As already remarked, the Wisconsin speci- 

 men differs from this figure in the following respects: Long genital 

 canal between genital pore and atrium; more elongated penis papilla 

 and seminal vesicle; and different shape of the seminal receptacle. 

 These differences, however, seem to result from a less contracted 

 condition of the parts than in Bendl's figure and do not appear to 

 justify the creation of a new species or subspecies, especially as the 

 European specimens vary considerably in color and sexual anatomy. 

 In view of the wide distribution of R. terrestris in a variety of locali- 

 ties in Europe, its invasion into the United States is perhaps not 

 surprising. 



