DESCRIPTIONS OF GENERA AND SPECIES 263 



Spirosperma papillosus (KESSLER). 



Nais papillosa, KESSLEB, Trud. Russk. Est. St. Petersb., 1868, p. 105. 

 Spirosperma ferox, EISEN, Bih. K. Svensk. Akad., 1879, No. 16, p. 10. 



Definition. Length 15 mm. Dorsal setae capilliform and pectinate ; ventral setae uncinate, 

 some of them with two or three denticles. Nephridia without vesicular cells, no terminal 

 dilated sac. Hab. Europe. 



The probable identity of EISEN'S Spirosperma ferox with Nais papillosa of 

 KESSLEB was pointed out by EISEN himself; and VEJDOVSKY (24, p. 45) suggested 

 that GBUBE'S ' Saenuris velutina ' may be identical. Both are placed as synonyms by 

 STOLC. Nevertheless, according to GEUBE, Saenuris velutina has nothing but capilliform 

 setae in the dorsal bundles, and the clitellum extends from segment ix-xii. Influenced, 

 no doubt, by these differences in the descriptions of the two species, VAILLANT doea 

 not unite them, but places GRUBE'S worm in the genus Tubifex. BENHAM has 

 described and figured the webbed setae of this species (9). 



Genus TELMATODRILUS, EISEN. 



DEFINITION. Setae all uncinate. Brain concave in front with a narrow process 

 posteriorly. Circumoesophageal blood-vessels of segments VII-XI contractile. 

 Integumental vascular system developed. Spermiducal gland furnished with 

 numerous (8-10) prostates ; penis chitinous. 



This remarkable genus has been only seen and described by EISEN ; it consists of' 

 but one species. EISEN places it in a special subfamily, that of the Telmatodrilini ; 

 but a further splitting up of the Tubificidae seems hardly necessary. The most 

 distinctive peculiarity of the genus is undoubtedly the numerous prostates; but 

 except for this the efferent apparatus shows no difference from that of Limnodrilus 

 and Spirosperma. The contractility of the anterior perivisceral blood-trunks is shared 

 by the genus Branchiura, but in Telmatodrilus only one of these pairs of vessels 

 that of the eleventh segment is larger than the rest. The approximation of the 

 dorsal ventral vessels upon one side of the intestine, is also something like what is 

 found in Branchiura; so too the integumental vascular network; in this respect, 

 however, Ilyodrilus and, to a less extent, Limnodrilus, resemble Telmatodrilus. 

 The spermathecae are a pair of simple oval pouches, which open between the dorsal 

 and ventral setae bundles in the tenth segment an anomalous position for the 

 Tubificidae. 



