622 



NATURE 



[October 27, 1892 



seta are in four couples, the individuals of which are near each 

 other. The girdle covers segments 29 to 37, while 31 : 33 : 35 

 bear each a pair of tubercules (Fig. 2) as in the green worm 



Fig. 2. — Diagram of girdle of A. cambrka. Friend, showing tubercula on 

 ventral surface. 



i^A. chlorotica). There are two pairs of spermathecse in seg- 

 ments 10 and II, opening anteriorly ; the male pore on segment 

 15 is borne on prominent papillae, which cause the adjoining 

 segments to appear swollen (Fig. 3). It is a very clean worm, 



Fig. 3 — Allolobophora cainhrica. Friend Natur-il size. 



exudes but little mucus as compared with the green worm ; the 

 tail is much longer than in that species, which, in the matter of 

 girdle and tubercules, it most nearly resembles. It will be well 

 to tabulate the points in which this worm resembles and differs 

 from its nearest allies. 



Allolobophor 

 Alio, chlorotica 

 in position and appearance of 

 male pore, girdle, and tubejxula 

 pubertatis. 



cainbrica resembles 



Alio, mucosa 

 in colour, shape, size, activity, 

 position of first dorsal pore, 

 and appearance of male pore. 



It differs 



in mucus, transparency, length 

 and shape of tail, and number 

 of spermathecae. 



in position and shape of girdle, 

 position of ttibercula puber- 

 tatis, and general outline. 



Tabular View. 



When our knowledge of the hybridity of worms is more per- 

 fect, it is possible that some new light will be thrown upon such 

 coincidences as these. I have received the worm from, or col- 

 lected it in, Nottinghamshire, Hertfordshire, Yorkshire, and 

 Montgomeryshire. I believe I have also found it in Westmor- 

 land and elsewhere, but entered it either under one or the other 

 of the two species which it so closely resembles. 



Next, we have to note the worms which are new to Britain, 

 though not new to science. These all fall under the genus 

 Allolobophora, and several of them are so well marked that I 

 have, in some recent articles on this subject, revived Eisen's 

 subgeneric term Dendrobsena, and placed under it about half-a- 

 dozen species of tree-worms which are more or less widely dis- 

 tributed in this country. 



The tree-worms are small, hardy, and active ; the lip is usually 

 very delicate, and appears to be used, not only as a sucker and 

 boring agent, but also as a tissue dissolver, probably by the use 

 of a special saliva. The setae are usually in eight almost equi- 

 distant rows, and the lip cuts more or less deeply into the first 



NO. 1200, VOL. 46] 



ring. The type of this group is Dendrobcena Boeckii, Eisen. 

 which has been the subject of endless confusion. The true 

 species, following the diagnosis of Eisen, is very rare in Eng- 

 land, and I have found it nowhere but in Airedale and Wharf- 

 dale, Yorkshire. I believe all the other records which have 

 been given by other writers should be assigned to the much 

 more common and widely distributed species known as Allolobo- 

 phora subrubicunda, Eisen. This worm belongs to the same 

 group, but lives among vegetable debris, as well as beneath tin- 

 bark of decaying trees. Another species (A. arborea, Eisen 

 is found only in dead timber. I have specimens from Cumber- 

 land, Gloucestershire, Yorks, and Sussex. It is one of the prettiest 

 and neatest worms indigenous to this country. Nearly related 

 to this is another (^. celtica, Rosa), which, while it prefers trees, 

 will thrive among decaying vegetable matter. I first found it 

 at Langholm, N.B., some two years ago, but since then I have 

 taken it plentifully in Carlisle, Morecambe, and Tunbridge 

 Wells, besides receiving it from Sussex, Devonshire, Gloucester- 

 shire, Northants, and elsewhere. It bears spermatophores 

 during the spring months. 



When I was in the south of England in the early months of 

 this year, I discovered a couple of specimens of a new British 

 tree- worm {A. constricta, Rosa). This species seems to me to 

 belong to the south, just as D. Boeckii belongs to the north. 

 I am inaking notes on the distribution of these species in order 

 if possible to ascertain their limits. A very anomalous worm 

 {Lumbricus Eiseni, Levinsen) belongs to this group, though it 

 has certain Lumbricus affinities. It is far from being a true 

 Lumbricus, since it possesses neither tubercula pubertatis nor 

 spermathecse. Its girdle, too, is abnormal, for, whereas in the 

 genuine Lumbricus the girdle invariably covers six segments, in 

 this worm it extends over eight or nine. At present it does not 

 fit in to any known genus, and should probably be made the 

 type of a new genus. I have found it in Carlisle, Gloucester- 

 shire, and Sussex. Rosa has obtained it in Italy, and Levinsen 

 in Copenhagen ; so that it appears to be very widely distributed. 

 On the Continent one or two further species belonging to this 

 group are on record. On account of their habits, size, and 

 affinities I place them in the subgenus Dendrobsena, which may 

 be presented in tabular form as follows : — 



Tabular View op Subgenus Dendrobcena. 



Boeckii, Eisen 

 Subrubicunda, Eis. 

 Arborea, Eisen . 

 Eiseni, Levinsen., 

 Constricta, Rosa... 

 Celtica, Rosa 



Segments occupied 

 by the 



29-33 

 26—31 

 27—31 

 24—32 

 26 — 31; 

 30-36. 



Tuber- 

 cula. 



First 

 dorsal 

 pore. 



31: 32: 33 



28 : 29 : 30 



29: 30 



Pro- 

 stomlum. 



4 close 



pairs 



4 pairs 



4 wide 

 pairs 



Cuts f peri- Dark brown 



stomium ] 

 Cuts one'Rose red, 



half I fleshy 



Cuts one j Red brown^ 



half i iridescent 



Cuts the Violaceous. 



whole j iridescent 

 Cuts one Rose red, 



half 1 fleshy 



Cuts oneiVioIaceous, 



half ruddy 



Another group of worms belonging to the genus Allolo- 

 bophora, with features more or less similar to those of the 

 typical earthworm, has recently been enlarged by the addition 

 of two or three species. The first {A. profuga, Rosa) seems to 

 be generally distributed throughout England, as I have re- 

 ceived it from several localities. Its synonymy, however, is at 

 present somewhat uncertain. The long worm {A. longa, Ude) 

 is the most ubiquitous of all our native species, and has for 

 years past been confused with the common earthworm. The 

 other species must for the present be entered as A. complanata 

 (Duges). The Continental authorities differ in their judgment 

 respecting the identity and synonymy of this worm, and I have 

 hitherto been unable to disentangle the complications. Certain 

 it is that we have a species which corresponds in part with the 

 worm described imperfectly by Duges, and I hope in a little 

 time to be able to determine its exact relationships. 



I append a list of all those species of British earthworms 

 which I have personally collected, examined, and identified ; in 



