ACTINIARIA 



43 



cases erroneously. I have only been able to examine a specimen imperfectly, mainly in the region of the 

 scapus. Though my observations need completing, I think that they may aid to characterize the species. 



The ectoderm of the scapus is very tliin in comparison to the mesogloea, the periderm tliick, and 

 the small nemathybomes provided with (rather sparse?) nematocysts of a length of about 31 — 36/^ and a 

 breadth of (2) 2.5//. The nematocysts were commonly not well preserved. Danielssen has reproduced a 

 section through the scapus (PI. 19, fig. 7) giving a rather good figure of the scapus. The nematocysts of the 

 tentacles are 24 — 27/.! in length and 2.5 /j in breadth, their spirocysts vary from 14 x 1.5/^ to 26 X 2.5 /j. 

 The ectoderm of the scapus is provided with numerous gland-cells, the nematocysts of which are 36 — 46 X 

 2.5—3 H- 



The longitudinal pennons of the mesenteries are rather strong, in tlie region of the ciliated tract with 

 about 15 — 20 folds, somewhat richly branched, especially in the outer part. The innermost fold is longer 

 than the largest one of the middle part. The lamellar outer part of the mesen- 

 teries are attached to the pennon close by its outer edge (textfig. 39). The 

 parietal muscles were not well preser\'ed, strong with rather numerous, long 

 folds, running parallel to the column. Their expansion on the column is 

 probably the ordinary one, but it is difficult to decide, on account of the 

 strong contraction of the muscles. The ciliated streaks are of the usual 

 structure. 



Remarks. The anatomical figures 8 and 9, PI. 19 in the work of 

 Danielssen are quite useless. The figure 9 illustrates nothing, and as to 

 the figure 8 it need hardly be said that the capitulum and the actinopha- 

 rynx are not sectioned, as declared by Danielssen, but only the scapus, 

 of which one part is involved. Tliis confusion of the body-parts also ex- 

 plains Danielssen's statement that the capitulum has papillae. In many other respects Danielssen's 

 description is certainly wrong, for instance his account of the actinopharynx and of the reproductive 

 organs, as well as his discover^' of acontia. 



Textfig. 39. Edwardsia jusca. 



Transverse section of pennon in 



the ciliated tract. 



Edwardsia andresi Dan. 



Edwardsia andresi n. sp. Danielssen 1890 p. 106, PI. 5, fig. 5, PI. 20. 



— — Dan., Appellof 1893 p. 12, PI. 3 fig. 19, Carlgren 1904 p. 542—543 fig. 8, Carlgren 



in Nordgaard 1905 p. 158. 

 Diagnosis. Physa well-developed, perforated by apertures. Scapus with a thin, easily deciduous 

 periderm. Nemathybomes accumulated in the middle Une of each compartment, but not forming a single, 

 longitudinal row. Nematocysts of the nemathybomes 48 — 67 X 3-5—4 /^. those of the capitulum 10 — 12 /i 

 in length. Tentacles 12, seldom 13 — 15. Nematocysts of the tentacles numerous, 24 — 29 (34) X 2 — 2.5 ji, 

 their spirocysts numerous, from 12—14 X i— i-S// to 26 X 2.5 /i. A weak ventral siphonoglj'phe. Typical 

 nematocysts of the actinopharynx (29) 36—43 X 3.5—5 l^. nematocysts with distinct basal part to the spiral 

 thread 24 — 29 X 4—5 ,«. Longitudinal muscle-pennons of the mesenteries strong, in transverse-sections of 



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