ACTINIARIA 



205 



Dimensions: Spec, i) diameter of the body a little above the pedal disc 4 cm, height 3 cm. Inner 

 tentacles about i cm long and broad. The specimen 2 was smaller, but more strongly contracted. 



Occurrence: 64°53' N. io°o' E. 630 m. Temp, at 600 m. — 0,69 (Michael Sars-Exp. 1900 St. 10) 

 I sp. (Sp. I). 

 Norway-Bear Isl. 73°27' N. 23°!!' E. 460 m. Black, gray clay. Temp, at the 

 bottom 2,67 (Swed.-Spitsberg.-Exp. 1898) i sp. (Sp. 2). 



Exterior aspect: The pedal disc was wide, in specimen i for the greater part torn off, so that 

 only the outer part was left. The body of specimen i was in contracted state conical, of specimen 2 more 

 cylindrical, the distal part of the body of spec. 2 

 bending outwards and downwards. The ectoderm 

 of the column was lost, the thick mesogloea shows 

 irregular, longitudinal, indistinct furrows. The 

 margin is tentaculate. The tentacles, partly cover- 

 ed by the column, are conical, about as long as 

 broad, and irregularly, transversally wrinkled. The 

 inner are considerably larger than the outer and 

 show no basal tliickenings at the outside. The 

 number of tentacles was in specimen i 

 about 90, probably 92, in specimen 2 104. 

 The tentacles are ver>- close and some- 

 times almost fusing together at the 

 base, especially in spec, i), so that the 

 outhnes between them are indistinct; 

 in such cases the mesenteries reach into 

 the tentacles, as textfigure 195 shows. 

 The oral disc is rather wide and ra- 

 dially sulcated. The actinopharynx is 

 well developed, with the deep siphono- 

 glyphes being devoid of gonidial tu- 

 bercles, but aborally prolongated. The 

 actinophar>'nx is besides longitudinallj- 



Fig. 197 



Fig. 196 



Textfigs. 195 — 197. Pycnanthus densiis. 

 Fig. 195: Transverse section of the basis of two tentacles [T). mc : mesentery, 

 sulcated, in specimen 2 there are about Figs. ig6 — 197: Transverse sections of the oral disc fig. 196 in the outer fig. 

 . . 197 in the inner part. 



12 longitudinal furrows on each side. 



Anatomical description: The ectoderm of the column is lost, its mesogloea is fibrillar and 

 provided with numerous, small, branched, protoplasma-poor cells. The sphincter is strong, and in the distal 

 part it almost fills up the whole breadth of the mesogloea, but rather soon decreases. It is on transverse sections 

 reticular and recalls the sphincter of Stomphia coccinea, though it is less strong and less long. I have not ob- 

 ser\'ed any distinct stratification of the sphincter. The ectoderm of the tentacles is rather high and contains 





X 



4 



