KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 63. N:0 7. 37 



Between Little Cumbrae and Millport, mud. Sept. 12 th , 1912. 



1 small specimen with 19 setigerous segments has the 7 th setigerous segment very long, i. e. here 

 — just as little as in the preeeding specimen — \ve do not see the segmental limit described in the 

 species as fairly near to and behind the parapodia of the 7* h setigerous segment, but a posterior 

 one in front of the glandular band of the 8 th setigerous segment. This segment is t hus rather 

 short, but with the parapodia somewhat behind the middle. Large ocelli are visible, some few 

 of theni in front of the mouth, but none on the outermost point of the head; in addition on each 

 side of the mouth along at least a quarter of the cephalic plate there are fairly numerous ocelli. 

 Nos. 3, 6, 9, 12, 16, 19, 23 and 26 are long anal cirri; nos. 12 and 26 are shorter than all the 

 others. There are altogether 27 anal cirri. 



South Devonshire: Salcombe, muddy foreshore, in front of Marine Hotel, Sept. 

 1908. Potts, 10 specimens a— j, 6 of which (a — f ) are complete and ha ve 19 setigerous 

 segments. 



a) Typical anterior limit between the 7 th and 8 t}l setigerous segments; few ocelli; size 112 x 

 1 mm. The glandular band of the 8 th setigerous segment irregularly completed anteriorly on the 

 lower side. The posterior end quite normal. 



b) 7 th and 8 th setigerous segments typical; no ocelli. 



c) = b); size 134 X 1 mm.; posterior end fairly normal, limit (i. e. anterior) between the 

 7 th and 8 th setigerous segments somewhat winding underneath, glands along the ventral nerve- 

 cord with a distinct break here, e. g. at the limit between the 8 th and 9 th setigerous segments. 

 Glandular band on the lower side of the 8 fh setigerous segment somewhat bending anteriorly. 

 Posterior end fairly normal. 



d) Between the 7 1 ' 1 and 8 th setigerous segments there is only a posterior limit somewhat curved 

 forward in the ventral middle line by the glandular band, which is somewhat irregular here. 

 The posterior end is almost normal, but there are 4 long anal cirri on the left side. No ocelli 

 were observed. 



e) The limit between the 7 th and 8 th setigerous segments about = d), but the forward curved 

 part of the glandular band is somewhat pointed. Posterior end fairly normal, but the ventral 

 cirrus is somewhat wider and there are in addition 4 long anal cirri on the right side. Ocelli 

 fairly few, but distinct. 



f) The limit between the l th — 8 th setigerous segments about = cl), but the glandular band is 

 also bent weakly outwards anteriorly above; posterior end normal; no ocelli. 



g) Straight posterior limit between 7 th and 8 th setigerous segments; no ocelli. 

 h) = g), but uncertain as to whether ocelli are absent or not. 



i) = h), but an anterior limit between the 7 th and 8th setigerous segments can be traced. 



j) Posterior end; anal cirri = e). 



With regard to the occurrence of more or less numerous specially fine anterior capillary setae 

 the following is to be noted. Specimens a — c have numerous setae of this sort on the 8 th and 9 th 

 setigerous segments, and specimen b, which as a matter of fact has less of the setae on the 8 th 

 setigerous segment than on the 9 th , has them on the 7 th setigerous segment as well. 3 of the other 

 specimens, all rather large, have such setae only on the 9 ih setigerous segment; in addition mostly 

 very numerous, up to 70 — 100 in one parapodium. The posterior capillary setae seem to be far more 

 numerous in the parapodia that have fewer, than in those that have more, fine anterior capillary setae. 



Salcombe. Aug. 11. 1900. Mar. Biol. Ass. 4 specimens, a— d, one of which, a, has 

 only 18 setigerous segments, but still no supernumerary posterior achaetous segment; 

 b has 19 setigerous segments. 



a) No ocelli, size about the same as the following spec. Limit between 7 th and 8 th setigerous 

 segments uncertain, but presumabbv an irregular anterior one. The posterior end normal. 



