TREE- wo RMS OF GREAT BRITAIIT, 297 



arrangement, and that while undoubtedly every true Lumhricus 

 has the peristomiutn completely divided by the hinder process of 

 the prostomium, yet not every worm with this feature is a true 

 Lumbricus. "Want of attention to this fact has led to further 

 confusion in the case of a recently discovered worm whicl. 

 Levinsen has described as Lumhricus Eiseiii. This worm, which 

 was first described from specimens found at Copenhagen, has 

 been obtained by Tlosa in Italy, and by myself in various parts of 

 Grreat Britain ; and is a true Dendrohcena, notwithstanding the 

 fact that it has the buccal arrangements of a typical Lumbricus . 

 In colour and in the disposition of the setae it somewhat closely 

 resembles Lumbricus purpureus, Eisen, but there the resem- 

 blances end. The true Lumbricus has always six girdle segments, 

 in this worm there are eight or nine. In Lumbricus the tuber- 

 cula pubertatis stretch across the four inner segments of the 

 girdle, here they are absent, or if present their position is ab- 

 normal. In Lumbricus there are two pairs of spermathecse, in 

 this worm they are entirely wanting. Lumbricus emits no yel- 

 low fluid ; this species does, though not always. Lumbricus is a 

 true earthworm, this is as truly dendrobaenic. Surely these are 

 characters which cannot be ignored, and show conclusively that 

 the mere shape of the prostomium is an insuflBcient generic 

 character unless accompanied by others which are permanent. 



We are now in a position to consider the several British 

 species of the subgenus Lendrobcena which have so far been 

 observed and described. 



Genus Allolobophoea, § Dendeob^na = Group No. 3 of 



Eosa's Classification. 

 1, A. (Dendeob^na) CELTIC a, B,osa. (PI. XXI. figs. 8, 9.) 

 Prostomium only partially dovetailed into the peristomium. 

 Individual setae somewhat widely separated. Length 1 to IJ 

 inches, of a dark brown or violaceous colour dorsally, tending to 

 iridescence ; lighter on the ventral side. Ciitellum flesh-coloured, 

 dirty yellow, or grey, and depending considerably on the habitat, 

 occupying 6 segments (31-36); tubercula pubertatis on 33-34. 

 Male pore on segment 15, borne on papillae which extend to 

 segments 14 and 16. In adult specimens segments 9, 25, and 

 26 also have glandular tumidities or papillae. Pirst dorsal pore 

 between 5 and 6. Copulatory setae on segments 31, 32, 35. 

 About 100 segments. 



