ARICIA NORVEGICA. 507 



Drobak, Norway (Sars). Station XL VII, off the coast of New York (' Challenger'), 

 at the great depth of 1340 fathoms in bine mnd. Also in 1200 fathoms off Rio, San 

 Francisco, in mnd. Jan Mayn (Hansen). Variety from the ' Valorous ' Expedition, 1875. 

 Bergen, Norway (Canon Norman). 



Head (Plate LXV, fig. 3) a short cone as in other species. 



Body typical in outline. The anterior region consists of fifteen bristled segments 

 (Sars says fifteen to sixteen). The branchiae commence on the fifth bristled segment. 

 The general aspect of this (anterior) region differs from that of the allied species (1) in the 

 flattened condition of the dorsal cirrus, which occasionally has a filiform process at its 

 outer edge ; (2) by the pallor of the anterior rows of ventral bristles and the large dark 

 brown spines of the last three or four ; (3) by the more acutely pointed papillae in the 

 row behind the foot (ventral division) and the tendency to show a larger area of bristles 

 and flap. Along the dorsum is a series of brownish dots at the segment- junctions, but 

 these were not observed in the spirit-preparations. 



The proboscis forms a frilled button like a rosette, the folds passing to the central 

 aperture. 



The first foot has two papillae, each with a short tuft of tapering camerated bristles. 

 The foot is thus bifid from the commencement, a condition not always seen in allied 

 families. At the tenth foot (Plate LXXXVII, fig. 2) the dorsal cirrus has a broadly 

 lanceolate outline with a long tip, and the shafts of the long bristles are smooth, the 

 tapering tips being camerated (Plate LXXXV, fig. 9). The bristles of the inferior 

 division form a dense series, and are short, tapering, and camerated. The posterior 

 papillae have tapered tips. The twelfth, thirteenth, fourteenth, and fifteenth feet show 

 numerous dark brown hastate spines (Plate LXXXV, fig. 9 a) ; the posterior papillae are 

 sometimes bifid. One of the spines (the upper) usually projects freely. 



Amongst the dorsal bristles are some bifurcate spinous forms (Plate LXXXV, fig. 



9 b). 



The anterior branchiae form broad, tapering, flat processes, nearer each other than 

 behind, where they are considerably longer and narrower, and leave much of the dorsum 

 bare. Posteriorly they greatly increase in length and have filiform tips. 



At the twenty-fifth foot, which shows the average condition after the change, 

 a considerable interval occurs between the branchia and the dorsal division, which has 

 four or five spines and a long tuft of slender bristles with very finely tapered smooth tips. 

 The cirrus is narrower and has a long tapered extremity. The ventral division has one 

 spine and a small group of equally slender bristles, the tips of which, however, are serrate. 

 The blunt setigerous lobe has a conical lobe to its outer side, whilst at its base externally 

 is a ventral cirrus, also of a conical outline and approaching the former in size. 



Tauber 1 (1879) appears to think that the Aricia Kujpfferi of Ehlers is a variety of 

 this form which certainly agrees with it in the absence of the cirrus between the dorsal 

 and the ventral divisions of the foot. Both have a similar ventral cirrus, and the general 

 characters agree except that the ventral surface of A. norvegica has no rows of papillae, 

 whereas that of A. Kupfferi has. The absence of the intermediate cirrus just referred 



1 ' Armulat. Danic./ p. 106. 



