ACTINIARIA 



Bismarck Strait. 7858',5 N. 2O35' E. 35 m (Romer & Schaudinn-Exp. St. 45). 



Unicorn Bay. 784o' N. 2i3i' E. 60 m (Romer & Schaudinn-Exp. St. 46). 



Great fiord, Changing point. 78i5' N. 2oo' E. 105 nom. (R6mer& Schaudinn- 

 Exp. St. 6). 



W. Thymen Strait. 78i4' N. 2i45' E. 38 m (Romer & Schaudinn-Exp. St. 47). 



Ryk-ys-Islets. 7749' N. 25i2' E. 60 80 m (Romer & Schaudinn-Exp. St. 49). 



West Spitzbergen. Bell Sound. 30 35 fms. (Torell). 



Norway Bear Island. 7253' N. 2i5i' E. 408 m. Bottom temp. 1,5 (Norw. N. 



Atlantic-Exp. St. 323). 



Exterior aspect: The pedal disc is wide and irregularly folded, there are sometimes traces of radial 

 furrows. The middle part is often, as in the anterior species, extended in a tap-like formation. The limbus 

 is well marked. The form of the column varies with the different state of contraction and is now cylindrical, 

 now narrower in the middle part with proximal and distal end broader (PI. 2 fig. 5) . The column is in con- 

 tracted state wrinkled and the margin rather well marked. The tentacles are short, cylindrical, pointed at 

 the apex, in contracted state irregularly wrinkled or longitudinally sulcated. The inner are considerably 

 thicker and longer than the outer. Already in small specimens the number of tentacles exceeds the maximum 

 of tentacles in St. coccinea. The number of tentacles f. inst. was 87 in a specimen, the pedal disc of which was 

 0,7 cm broad and the column 0,9 cm high. The number of tentacles was commonly between 95 and 115, 

 the latter number in a specimen of which the pedal disc was 0,6 cm and the height of the column 1,4 cm. 

 The tentacles were arranged in 5 cycles, 6 + 10 + 16 + 32 + 64, of which the last was imperfect. The oral 

 disc is wide and provided with radial furrows, corresponding to the insertions of the mesenteries ; the furrows 

 appear most distinctly in the outer part of the disc. There are besides indistinct transversal furrows, arisen 

 by contraction. Two distinct gonidial tubercles are present. The siphonoglyphes are broad and aborally 

 prolongated. The actinopharynx is distinctly longitudinally sulcated, on each side of the direction plane 

 about 14 furrows appear. 



Anatomical description. The ectoderm of the column is rather high and contains few nemato- 

 cysts, about 17 X 1,5 ft. large. It forms a cuticle which may be incrusted with foreign bodies, probably kept 

 together by the secretion of the mucus cells. This cuticle, which does not reach any greater thickness, however 

 seems to be easily thrown off, as it is wanting in the specimen reproduced in the figure PI. i). The sphincter 

 is reticular as in St. coccinea, now shorter now longer, according to the state of contraction. The distribution 

 of the sphincter, the muscles of the tentacles, and those of the oral disc agree with those of the anterior species. 

 The nematocysts in the apex of the tentacles are 24 31 x 2 2,5 p in size, in the proximal part a little smaller. 

 The spirocysts vary in size from about 19 x 1,5 ft to 53 x 3,5 4,5 ft. I have not observed any large specific 

 nematocysts in the maceration preparations of the numerous, examined specimens. In a single, small specimen 

 from Changing point I have, however, found such capsules in rather great numbers. Such capsules either 

 very seldom occur, or this specimen is a hybrid coccinea & polar is with the same number of tentacles as in 

 polaris and with large nematocysts as in St. coccinea. The supposition that we here have to do with a hybrid 



