DESCRIPTIONS OF GENERA AND SPECIES 693 



A. minima, xxxiii-xxxvii. The separation here is not only quite as far but further 

 than that between Allurus tetraedrus, xxii-xxvii,, and AUolobophora Japonica, 

 xxiv-xxxi. As for the fewness of the segments included in the clitellum of AUurus, 

 AUolobophora studiosa has only six segments in its clitellum, a number only greater 

 by one than the number found in AUurus ninnii. 



In specimens of AUurus from Teneriffe and from New Zealand, I have found 

 that the clitellar setae have a peculiar form which is characteristic; the free 

 extremity of the seta has a spear-head termination; I do not know how far this 

 really distinguishes the species AUurus tetro.edrus of the genus AUurus in general 

 from AUolobophora; but if it is not to be found in AUolobophora or Lumbricus, 

 then it appears to me that this character, coupled with the position of the male 

 pores upon the thirteenth segment, is perhaps enough to distinguish the genus. 

 In any case the genus AUurus will be retained here as thus defined. In default 

 of any information as to the internal structure of Tetragonurus, I shall retain that 

 genus also. 



Quite recently Moore has introduced a new genus under the name of Bimastos. 

 The clitellum (xxiii-xxviii), absence of spermathecae, and position of male pore (on 

 xv) show that the genus is a Lumbricid; but the author speaks of a pair of large 

 glands communicating with the male pore. If these are anything more than the 

 swollen integumental crests which surround those pores in most other Lumbricidae, 

 the genus may be distinct. 



The number of species belonging to the three genera of the Lumbricidae is very 

 large ; but the number of names given is, of course, considerably in excess of this. 

 Vaillant gives descriptions of no less than fifty-eight species, which he regards as 

 identifiable; thirty-six are enumerated, which are either placed as 'incertae sedis,' or 

 are termed ' Lumbrici dubii.' Since Vaillant's work has been published about thirty 

 genuine species of these genera have been added to the list by Mighaelsen and Rosa. 

 The list of Vaillant can be reduced considerably and without any doubt. He includes 

 a number of species which are most obviously not Lumbricus or AUolobophora ; a few 

 other species, too imperfectly described by their original describers, have been shown 

 to be wrongly placed in any of the genera which compose this family; the list may, 

 finally, be reduced by eliminating a number of species 'which are certainly members 

 of the family Lumbricidae as here defined, but are for various reasons no longer 

 recognizable. It will be advantageous, I think, to treat of those in the present 

 chapter, and not encumber the description of the species with discussions as to the 

 identity of various forms, concerning which there is really not sufiicient evidence. 

 Where there is, in my opinion, clear evidence as to the identity of a species 



