DESCRIPTIONS OF GENERA AND SPECIES 247 



In a species of Limnodrilus from New Zealand there are two pairs of dilated 

 hearts in precisely the same segments (viz. viii and ix) as those in which these 

 hearts occur in Clitellio. This lessens the gap between the two genera. It should, 

 however, be mentioned here that the specimens of Limnodrilus novae-zelandiae 

 examined by me were sexually immature. It is therefore, perhaps, begging the 

 question to refer them to the genus Limnodrilus, which I do on account of their 

 fresh-water habitat. 



VAILLANT (6) enumerates nine species of Clitellio of which some are apparently not referable to 

 this genus ; Clitellio benedii is, as is pointed out elsewhere, a Hemittibifejc ; MICHAELSEN (6) assigns 

 Clitellio Jineatus to the genus Pachydrihts. I discuss this view below. So, too, Clitellio minutus. 



Clitellio inaequalis, described by 0. F. MULLER as ' Lumbricits ' itiaequalis, and doubtfully referred 

 by GRUBE (8, p. 104) to this genus is a difficult species to come to any conclusion about. All that 

 MULLER says about it is ' Papillis lateralibus simplicibus ; setis solitariis.' VAILLANT justly remarks 

 that these characters are 'trop succinctement donneV to enable any conclusion to be drawn. The 

 papillae obviously suggest Hemitiibifex benedii. 



Clitellio tieurosoma of FREY and LEUCKART (p. 150) was referred by D'UDEKEM (1, p. 545, and 

 5, p. 12) to the genus Lumbricitlits ' a cause du developpement des vaisseaux lateraux du systeme 

 circulatoire.' These were described by the authors who named the species as being very long and 

 much convoluted, especially in the anterior segments. 



Clitellio tennis was described by LEIDY as a Lumbriculus (4, p. 148); VEJDOVSKY (24, p. 51) 

 places it among the Lumbriculidae but as 'incertae sedis.' VAILLANT (6, p. 421) doubtfully includes 

 it in the genus Clitellio. The position of the genital orifices (? male-pores) upon the tenth segment 

 (ninth in LEIDY'S enumeration) appears to justify its being put in the family Tubificidae, when 

 taken in connexion with the fact that the setae are uncinate and 3-6 iu a bundle. The habitat 

 as VAILLANT remarks is also in favour of the correctness of this identification. 



Clitellio irroratus of VERRILL (p. 324 and 622), called also a Clitellio by VEJDOVSKY (24, p. 45), 

 queried by VAILLANT (6, p. 422)3 is I imagine not a Clitellio ; as VAILLANT points out the presence 

 of capilliform setae in the dorsal-bundles is against this identification ; the fact that these setae 

 are not always present suggests the genus Hemitubifex. 



Clitellio dnbius of CzERNiAVSKY (p. 327) might be almost anything ; it is only known from a 

 fragment of the hinder end of body. There remains only 



Clitellio arenarius, SAVIGKY. 



Clitellio arenarius, SAVIONY, Syst. d. Annel., 1820, p. 104. 



Lumbricus arenarius, O. F. MuLLEB, Zool. Dan. Prodrom. 1776, p. 216. 



Lumbricus littoralis, BRUGUIKRE, Tabl. Encycl. I79I 1 - 



Peloryctes arenarius, LEUCKART, Arch. f. Nat. 1849, p. 161. 



Tubifex hyalinus, D'UDEKEM, Bull. Ac. Roy. Belg. 1855, p. 544. 



1 Fide VAIU.AXT. 



