. The Danish Ingolf-expedition. Marine animals -- Arctic regions; Scientific expeditions; Arctic regions. 226 ACTINIARIA figure of the sphincter of , reproduced by Kwietniewski (1898) — a species to my mind identi- cal with A. spetsbergensis — the sphincter seems to be ahuost alveolar. In sexually ripe specimens I have but rarely found traces of stratification in the middle part; this stratification is, ho\ve\'er, never as distinct as in Actinostola abyssorum and callosa. The mesenteries are arranged as in the type-specimen, which I have been able to confirm by several examined specim
. The Danish Ingolf-expedition. Marine animals -- Arctic regions; Scientific expeditions; Arctic regions. 226 ACTINIARIA figure of the sphincter of , reproduced by Kwietniewski (1898) — a species to my mind identi- cal with A. spetsbergensis — the sphincter seems to be ahuost alveolar. In sexually ripe specimens I have but rarely found traces of stratification in the middle part; this stratification is, ho\ve\'er, never as distinct as in Actinostola abyssorum and callosa. The mesenteries are arranged as in the type-specimen, which I have been able to confirm by several examined specimens. The longitudinal muscles of the strongest mesentery in the pairs of the third cycle face towards the mesenteries of the first cycle. In a single specimen, of which I have examined one half, two mesen- teries deviate from this rule, in as much as the longitudinal muscles face towards the mesenteries of the second order. The appearance of the mesenteries as for the rest agrees wHli that of the type-specimen. The size of the marginal stomata, however, varies considerably, some- times they are very large as in the reproduced specimen of .4. s/67'nca (Carlgren 1893b p. 233 fig. i), at other times they are small as in the type-specimen. The ciliated streaks were well developed and the meso- gloea of the filaments in the middle part provided with rather numer- ous cells. The reproductive organs start from the mesenteries of the third order; in a specimen I have, however, found a fertile mesentery of the second order. In a great part of the specimen the ova were large and few, in other parts numerous and smaller. This difi'erence is probably connected with the fact that the reproductive period in the first case had come to its close. I have in several specimens found young in the coelenteric cavity. Sometimes these young reach a considerable size (Carlgren 1893b, 1902 p. 47). The coelenteric cavity thus in this .species serves as a brood-room. As I have before mentioned (1902
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Keywords: ., bookcentury1800, bookdecade1890, booksu, booksubjectarcticregions
