318 



OLIGOCHAETA 



The principal reasons which lead Michaelsen to identify this species with Levinsen's Analycus 

 glandulosus are (i) the fusion of the prostomium with the buccal segment, and (2) (apparently) the fact 

 that the spermathecae are long sacs without diverticula ; there is, moreover, nothing in the diagnosis of 

 Levinsen which goes against the identification. 



Michaelsen found that the head pore was (exceptionally for the genus) placed 

 between the prostomium and the buccal segment. Sperm-sacs and egg-sacs appear 

 to be paired. 



(5) Mesenchytraeus flavus (Levinsen). 



Analycus flavus, Levinsen, Vid. Med. 1883, p. 232. 



Paehydrilus flavus, Vaillant, AnneMs, p. 245. 



Mesenchytraeus flavus, MiCHAELSEN, Abh. Nat. Ver. Hamb. 1889, p. 18. 

 Definition. Length, 15 mm.; iimally three setae in lateral and jive in ventral bundles. 

 Spermathecae with a single pear-shaped diverticulum ; funnel comparatively small ; sperm- 

 duct very short. Hob. — Nova Zembla ; Denmark. 



Michaelsen has identified an Enchytraeid found by him among three specimens 

 of ' Neoenchytraeus vejdovskii' as ' Analycus fiavus' ; he naturally adds something to 

 Levinsen's very short account of the species. The egg-sac is paired and extends 

 through at least segments xiii, xiv, xv. Vaillant, in copying Levinsen's diagnosis, 

 has fallen into an error, by omitting to mention the appendix of the spermatheca ; 

 he says that the spermathecae are ' formees d'un conduit long et etroit sans appendices 

 glandulaires et d'un sac pyriforme ' ; the latter is evidently the diverticulum and not, 

 as Vaillant's description would lead one perhaps to infer, the swollen end of the 

 pouch. The other characters of the species are to be found in the above definition. 



(6) Mesenchytraeus beumeri, Michaelsen. 



Paehydrilus Beumeri, Michaelsen, Arch. Mikr. Anat. 1885, p. 294. 

 Paehydrilus (Mesenchytraeus, Eisen) Beumeri, Michaelsen, Ench. Mob., 1886, 



p. 44 et passim. 

 Mesenchytraeus Beumeri, Michaelsen, Arch. Mikr. Anat. 1887, p. 372. 

 Definition. Length, 30 mm,. ; Setae, 3-5 in lateral, 5-8 in ventral bundles ^. Spermathecae 



' The actual numbers of setae are thus stated by Michaelsen : — 



