Ao The Irish Naturalist. 



Species belonging to the genus Allolobophora closely resemble 

 the true Ltwibrici, they may always be distinguished by the 

 shape of the hinder part of the lip, or its mode of insertion. 



It may be well to give an outline of the leading characters 

 of the genus. In Allolobophora the lip or prostomium only 

 partially bisects, or is dovetailed into the first ring or peristo- 

 mium (see page lo, fig. 2). The setae are arranged in four pairs 

 on each segment except the first, the individuals of each couple 

 being either close together or somewhat widely separated. 

 The girdle or clitellum is composed of a variable number of 

 segments — as few as four, and as many as eight or ten in 

 the British species (even more in some Continental forms), 

 commencing on the 26th or some more posterior segment. 

 The clitellar papillae {tubercttla pubertatis) are variable, being 

 sometimes on alternate, and at others on contiguous segments. 

 They may appear either as pores, as in the Green Worm {A. 

 chlorotica, Savigny), as a distinct band, or as prominent but 

 continuous protuberances. One species {A. profuga, Rosa), 

 forms a connecting link between this genus and the last, for it 

 has the head of an Allolobophora, with the typical girdle and 

 band of a Ltmibricus as already figured (page 10, fig. 3). The 

 male pores are on segment 15 as in Lumbricus, and are, I think, 

 without exception accompanied by papillae. The colour-range 

 is very much greater than in the other genus ; we have green, 

 steel-blue, clay, flesh, rose-red, red-brown, sienna-brown, and 

 brindled forms, to mention no others. As a rule there is little 

 if any iridescence. The first dorsal pore is either between 

 segments 3-4 or posterior to this. Spermathecae are absent, or 

 variable in number. Some of the species, notably the Green 

 Worm {A. chlorotica, Savigny) carry spermatophores. This 

 general outline will suffice for present purposes, a full tabular 

 statement being reserved for a later stage. 



Our next business is to ascertain how the different species 

 included in the genus are related, and what characters are 

 best suited for separating the whole into a few natural groups. 

 The work would be comparatively easy if we had to include 

 the European species with those which are indigenous to 

 Great Britain (all of which have now also been sent to me from 

 Ireland). As it is, we have one or two instances in which well- 

 defined groups are represented in these islands by only a soli- 

 tary species, and thus the sections may be made almost as 



