8 G. Eisen, 



The nervous system resembles more that of Tubificidœ. The supra- 

 oesophagialgaiigliou is broad and narrow, with both its margins deeply 

 emarginated. Fig. 10. The anterior one emits two pair of dichotomous 

 nerve-trunks. A distinct infra-oesophagialganglion, as that oï KhyncJielmis^) 

 hardly exists, or seems rather replaced by the first ganglionic swelling 

 of the ventral nerve. The first three ganglionic swellings are much 

 nearer together than the succeeding ones, and the lateral nerves of the 

 first two ganglia running more obliquely, than those of the others, which 

 are nearly rectangular with the ventral trunk. The first two ganglia 

 emit only two pair of nerves each, but all the other ganglia emit three 

 pair. Of those the first two are situated near the middle of the ganglion 

 and are nuich closer together, tlian to the third one, which is situated 

 near the posterior dissepiment of the segment. Fig. 10. PI. II. 



As in the other genera of Lumhriculidce the reproductive organs 

 are of two kinds: 



Male and female. 

 The male organs consist of: 

 1. Tetites & 2. Eß'erent dacts^ and the female ones of: 

 '?>. Ovaries, 4. Oviducts and 5. Bfceptacles. 



In Rliynchelmis^ F/ireatothrix, Lumbricuius and StyLodrilas the testes 

 reach a voluminous degree of development, often entirely filling the 

 segments they occupy. In Trichodrihis, Rhynchelmis and Flireatothrix they 

 always occur in pairs, but in Lauibriculas snd Stylodrilus they are mostly 

 single and only occasionally the first one is found double "). In all 

 the above genera their volumes seem to be more or less variable. In 

 Ocnerodrilus on the contrary we find always two pair of testes of rather 

 minute development and constant size. One pair is situated in the 8"* 

 setigerous segment, where it is affixed to the dissepiment between the 

 8"' & the 9"' segments. The second pair is found in the 10"" segment, 

 but is affixed to the dissepiment between the 9"' t\!; 10"' segments. Thus 

 we find the testes affixed to two consecutive dissepiments, but not in 

 two consecutive segments. The form of the testes is pretty regular and 

 nearly tlie same in both segments, and also in the difterent specimens. 

 Fig. 17. PL II. 



The arrangement of the spermatozoa is the same as that of the 

 ova; the largest ones being situated nearest to the upper margin of the 

 lobes. The smallest or least developed spermatozoa-cells resemble ex- 



') Vejdovsky, 1. c. Taf. XXI fig. 12. 



-) Claparèiie, liechorclics amit. s. Ollgocli. pug. .'iS. 



