DESCRIPTIONS OF GENERA AND SPECIES 617 



Genus Hyperiodrilus, Beddard. 



DEFiisriTiON. Setae paired, those of ventral pairs further apart than dorsal. Clitellum, 

 XIV-XVII. Male pore between XVII/XVIII ; two penes on segment in front or 

 further forward (position variable), connected by grooves with male pore. Sper- 

 matheeal pore on XIII. Gizzards in XVIII-XXIII ; calciferous glands in XII ; 

 pouches in IX, X, XI. Testes in XI (and XII?). Sperm sacs in XI, XII. 

 Funnels lie in XI, XII. Ko penial setae. 'Spermatheca small, enclosed within 

 large spermathecal sac, which surrounds ^ gut, and communicates with sacs 

 containing ovaries. 



This genus has, at present, been studied by myself only ; it contains but one species. 

 Of the external characters, the penes appear to be very characteristic ; it is also 

 a remarkable fact that they vary in position as iii Alvania and Stuhlmannia, the 

 only other genera in which a penis or penes are present. I found three variations; 

 in one specimen 'the two papillae, which I call penes, were symmetrical, and lay upon 

 the middle of the seventeenth segment, not very far in front of the male pore ; in 

 a second one the penis, the left-hand one, was on the border-line of segments xvi/xvii, 

 and was larger than the 'right-hand penis ; the latter lay at about the middle of the 

 seventeenth segment; in a third the two penes were but little prominent, and were 

 very closely approximated to each other and to the male-pore, forming altogether 

 a triangular swelling ; in every case the two papillae were connected by a groove 

 with the male pore ; the male pore usually did not present the appearance of a pore, 

 owing to the fact that the distal end of the bursa was slightly protruded. 



The male generative organs present some unusual features ; there appear to be 

 only a single pair of testes ; these are unenclosed in any sperm-sac, and are attached 

 to the sperm-duct as it issues from the tenth segment ; there may be a second pair ; 

 but, if so, it seems likely that they will be found in a corresponding position in 

 the twelfth segment. The fact is that here, as in Teleudrilus and a few other forms, 

 the sperm-ducts perforate the septum, whence depend the funnels, twice. The 

 sperm-duct, passing forwards, makes its way through one of the septa in question; 

 it then dilates into a wide oval sac, as in Teleudrilus, &c.; bending back, it again 

 perforates the septum, and opens into the interior of the segment by the funnel, or, 

 rather, into the sperm-sac which is attached to the anterior wall of the eleventh and 

 twelfth segments. The abnormal position of the funnels may perhaps be accounted 

 for by the pulling back of the end of the sperm-duct during the growth of the 

 sperm-sac; in any case, the sperm-sacs are, no doubt as in other worms, developed 



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