420 Hjalmar Ditlevsen 



St. 62. Stormbugt 



„ 63. 



„ 70. Danmarks Havn 



,; 71. Off Cape Bismarck 



,, 72. Stormbugt 

 This species is very abundantly represented; there are specimens 

 from all the stations mentioned, several from some of them and 

 many from one, namely St. 63. There are large and small individuals 

 and among them 4 epitokous forms, 3 of which were taken in July, 

 the 4th in August. Two come from Danmarks Havn and were taken 

 respectively on the 18th and 21st of July 1907 among the Laminaria 

 at a depth of ca. 8 — 16 m. The third specimen was taken in Storm- 

 bugt, pelagic among the drift-ice on the surface of the water, — 1 m., 

 and the fourth lastly comes from Hvalrosodden, where it was taken 

 near the beach drifting past in the current on August 20th 1906. 

 Two are females and the other two males. The two females measure 

 respectively 89 and 72 ram. in length; both lack some of the last 

 segments and have perhaps been about 1 cm. longer. The length of 

 the one male is 53 ram. and is complete, the second, which like the 

 females lacks some segments, measures 38 ram. The material is 

 naturally too small to be able to draw conclusions with regard to a 

 difference in size between the two sexes. Counting the untransformed 

 parapodia I found 21 in both the females; Michaelsen has 20, stating 

 that "21te Ruder zeigt die Umbildung fast vollendet". It is possible 

 that this feature varies somewhat in diiîerent individuals, as the 

 transition is not very abrupt between the untransformed and trans- 

 formed parapodia but extends over ca. 2 — 3 segments. In the males 

 I count 17 untransformed parapodia and find the 18th practically 

 completely transformed. The male individuals are more strongly 

 coloured than the females; how far this will prove to be the rule, I 

 can naturally not say. A second difference between the sexes seems 

 to lie in the size of the eyes, these in the males seeming larger and 

 more prominent. The first pair of eyes seem to be on the whole 

 larger in both sexes. The ventral margin of the dorsal cirrus is 

 toothed in the male, but not in the female. This, which seems to 

 be the general rule in the epitokous forms of the Nereis species, thus 

 applies also to this form. 



In ray report on the polychaetous Annelids of the "Frani" I have 

 stated, that it would possibly prove, that the two nearly allied forms 

 N. zonata and N. pelagica "durch Zwischenformen allraälich in ein- 

 ander übergehen", and I based this statement, among other things, 

 on some individuals in which the light transverse belts were very 

 indistinct. After going through the more copious material of N. zonata 



