424 Hjalmar Ditlevsen 



respect typical Scalibregma inflatum; only the bristles are extremely 

 long, silky and soft. In this regard they agree Avith Michaelsen's var. 

 corelhnira. They are all large individuals, of about 40 mm. in length 

 on an average. The only specimens of this species in the Museum, 

 Avhich exceed these in size, are some individuals from the Kara Sea, 

 taken by Тн. Holm on the Dijmphna; the largest of the latter has a 

 length of 85 mm., a size which suipasses all the statements I have 

 seen, hi his paper on the anatomy of the Scalibregma Ashworth 

 states, that his largest specimen, which measured 56 mm., "is one of 

 the largest specimens yet recorded". Compared with this the speci- 

 men from the Kara Sea is a perfect giant. I may remark, however, 

 that my measurements do not pretend to be completely accurate, as 

 the state of preservation of the animal did not permit of exactness ; 

 a portion of the posterior region for ca. 1 cm. is thin and pulpy, but 

 I have taken account of this and measured the length in such a 

 way, that my statement by no means exceeds the actual length. 

 The greatest thickness of the same individuals is ca. 15 mm. The 

 second specimen from the Kara Sea is a good deal smaller, but an 

 exact measurement can still less be given here, as a large piece of 

 the posterior part of the animal is wanting, probably some cm. The 

 part remaining is ca. 40 mm. That the size of this species varies 

 within very wide limits, as Ashworth 1. с p. 245 notes, I can confirm 

 to the fullest extent from the material in the Museum here, as also 

 that the species seems to have a surprising power to adapt itself to 

 different conditions. In the smaller, enclosed waters with slight 

 salinity the individuals seem to be very small. Specimens are pre- 

 sent from the Danish waters, the Skagerak, Kattegat, Hellebæk and 

 Baltic, and of these the Skagerak individuals are the largest whilst 

 the smallest come from the Baltic. 



In the Danmark Expedition's material there are some well-pre- 

 served specimens, which seem also to have kept their colour very 

 well. This in all individuals is distinctly yellow, a mixture of sulphur 

 yellow and light ochre. On the distended parts of the body the 

 colour is lighter, to almost whitish, and the males are on the whole 

 lighter than the females, especially on the parts where the genital 

 products shine through. The spermatozoa are white, namely, whilst 

 the eggs are distinctly yellow, in colour perhaps a little darker and 

 a little more reddish that the outer skin. The projecting proboscis 

 shows a characteristic, bluish-gray colour, which is also found on 

 the anal cirri. 



Of greatest interest, however, to my mind, in the specimens 

 brought home by the Danmark Expedition, is the manner in which 

 Ihey were taken. In two cases it is stated, that they were taken 



