ACTINIARIA 



pairs was in one half of the animal 3 + 3 + 6 + 8 = 20, in four compartments between the mesenteries 

 of the first and second order one pair of mesenteries of the fourth cycle was wanting. The mesenteries were com- 

 monly a little more numerous than the tentacles, in individuals with a greater number of mesenteries. In a 

 specimen with 18 pairs of mesenteries all were perfect, in specimens with numerous mesenteries at least one 

 half or more was perfect. The longitudinal pennons are strong and recall those of Urticina. Especially strong 

 pennons were developed in the specimen from Finmark. The parieto-basilar muscles are well defined, 

 broad, and reach to the sphincter. The basilar muscles are distinct and appear clearly under magnifying powers. 

 Oral and marginal stomata are present, the latter are small. 



The reproductive organs already appear on the mesenteries of the first order. In nearly all (4) by 

 myself examined cases the directive mesenteries were fertile, in one case sterile. 



I have not found any embryos in the coelenteric cavity of this species. The material is however 

 too small only three specimens were female, the other examined ones male (compare the table) - - for 

 deciding whether the young develop in the coelenteric cavity or not. On the other hand, there were in a spec- 

 imen from the station 67 (Michael Sars-Exp.) lots of embryos, embedded in mucus inside a circular fold below 

 the sphincter. I cannot with certainty decide, if we have to do with a species having the embryos attached 

 to the outside of the column as in Epiactis prolifera, or if lots of young have been ejected during the strong 

 contraction of the body, when the animal was killed. Nevertheless, the circumstance that there were 

 marks of the embryos upon the column inside the circular folds, indicating that the embryos have been 

 fastened there, speaks for the opinion that we have to do with a species, taking care of its brood. It would 

 besides be peculiar, if by an eventual squeezing out of the embryos during the preservation, all embryos 

 should have been ejected; on the contrary, it was to be expected, that at least a few had been left in the in- 

 terior, but this is not the case. I therefore believe that I am not erring if I suppose that C. spetsbergensis 

 is a species, taking care of its brood. 



Systematic remarks. This species is probably nearly related to Cribrina elegantissima. It is 

 possible, that Leiotealia spetsbergensis may be partly identical with my species. I conclude it hence, that 

 Kwietniewski (1898 p. 122) declares that he has found a brood-room in the most distal part of the column 

 of a specimen. However, Kwietniewski does not mention any verrucae. Besides, Leiotealia spetsbergensis 

 is not a homogeneous species (compare p. 175). 



Genus Cribrinopsis n. gen. 



Diagnosis: Cribrinidae with commonly feebly developed verrucae (or no?) on the column. Acro- 

 rhagi and pseudo-acrorhagi absent. Sphincter strong, palmate or pinnate. Tentacles simple, thick, cylindrical, 

 short. I/ongitudinal muscles of the tentacles principally mesogloeal. Radial muscles of the oral disc ecto- 

 mesogloeal. Numerous, perfect mesenteries decamerously, hexamerously, or irregularly arranged. Well devel- 

 oped mesenterial muscles. Reproductive organs on the mesenteries of the first cycle and on the other 

 stronger mesenteries, often not developed on the directives. Nematocysts in the ectoderm of the tentacles 

 and in that of the actinopharynx of about the same length. 



20* 



