I [39] OLIGOCH^TOLOGTCAL RESEARCHES. 917 



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funnel-shaped orifice, especially adapted for captuiing the spermatozoa. 

 This efferent funnel is mostly covered along its inner surface with vi- 

 brating cilia, protruding far outside its exterior margin. In Lininodril/us 

 alpestris and Camptodrilus spiralis, however, the cilia must either be very 

 minute or entirely absent, as I have repeatedly failed to observe them, 

 at least in the margin of the funnel. The funnel cilia of Eemituhifex are 

 longer than the funnel. The exterior of the efferent funnel is in Ilyodri- 

 lus Perrierii covered with dark oblong glands. In some species, such 

 as Spirosperma, etc., the cells composing the funnel are large and plainly 

 visible; in others again, such as Ilyodrihis fragilis, only the cell-nuclei 

 can be seen. 



The main body of the atrium consists of two separate layers or coat- 

 ings, one overlaying the other. Only the interior one of those extends 

 clear down to the apex of the penis. The exterior one, on the contrary, 

 does not extend farther than to the upper end of the penis sheath, and 

 ends here somewhat abruptly. Its lower continuation, from which it 

 was easily separated, forms the exterior sheath of the oviduct w^hen 

 such a sheath is present. When not present, it must either have been 

 absorbed or grown together with the interior oviduct, and forming what 

 I have here mentioned under the name of a single oviduct. Further 

 ahead in this paper I will endeavor to show how such separation has 

 taken i)lace and in what way the oviduct has originated. 



The form of the oviduct varies some in different genera, but not 

 enough to furnish good genus characteristics. In Telmatodrilus the 

 atrium is cylindrical, bent like a crescent, but not tapering towards the 

 ends. The atrium in this family is furnished with several distinct pros- 

 tate glands, cropping out, as it were, on all sides of the atrium. In 

 Tubijicini the form of the atrium is less regular, and resembles more an 

 oblong sack, more or less tapering towards both ends, especially towards 

 the penis. In Tuhi/ex this lower part of the atrium is shorter than in 

 any other genus. In Limnodrilus it is longer — longer even than the 

 upppr j)art, which is swelled. In Ilyodrilus the atrium is very irregular 

 and its form inconstant. In the same species it is sometimes consider- 

 ably extended, sometimes again contracted in length, and constricted 

 in several different places, however without forming anything like a 

 '■'■ vesicida seminalis.^'' 



From this general form of the atrium we meet with two notable ex- 

 ceptions : the one in Psammoryctes, the other in Hemetuhifex. In lioth 

 these genera the upper end of the atrium, which carries the prostate 

 gland, is enlarged and perfectly globular, and at least in form distinct 

 from the other part of the atrium. In Psammoryctes the lower end of 

 the atrium, or that part which is situated between the " globular cham- 

 ber " and the penis proper, is long, narrow, tube-like, and not glandular.* 

 But, according to E. Kay Lankaster, this peculiar tube should resemble 

 the corresponding part in Limnodrihis» If this is the case the tube must 



■ Vejdovsky, Ueber Paamnaoryctes, p. 145, 



