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APR eT 
A NEW BRANCHIATE OLIGOCH ATE. 325 
A New Branchiate Oligochete (Branchiura 
Sowerbyl). 
By 
Frank E. Beddard, M.A., 
Prosector to the Zoological Society of London, Lecturer on Biology at 
Guy’s Hospital. 
With Plate XIX. 
WE are acquainted at present with three genera of Oligo- 
cheta which render the Cuvierian name of “ Annélides 
abranches sétigéres” no longer applicable to the group. 
Dero has been known since the time of Rosel and Otto Fried- 
erich Miiller, the latter of whom recognised the branchial func- 
tion of the ciliated processes at the anal extremity of the body. 
Alma nilotica, originally described by Grube,! and lately 
reinvestigated by Levinsen,? is, according to Grube, much like 
a Rhynchelmis in general habit. It has paired sigmoid 
setee ; the posterior sixty segments or so are furnished with 
short dorsally placed processes, more numerous upon the an- 
terior than the posterior of these segments. The name given 
by Levinsen is Digitibranchus niloticus; but this worm 
is, in all probability, generically and specifically identical with 
Alma nilotica. The third branchiate form has been quite 
lately described in this Journal® by Professor A. G. Bourne. 
1 * Beschreibungen neuer oder wenig bekannter Anneliden,” ‘ Arch. f. 
Naturg.,’ 1855, p. 129. 
2 «Qm to Regnormslaegter fra Algypten,” ‘ Vidensk. Meddel. naturk. 
Foren.,’ 1859, p. 321. 
3 On Chetobranchus, a New Genus of Oligochetous Chetopoda,” 
‘Quart. Journ. Micr. Sci.,? vol. xxxi, p. 83. 
VOL. XXXIII, PART III].—NEW SER. Z 
