CERIANTHARIA. 



23 



them as being darker than the marginal ones, and marked with white longitudinal lines. In the 

 Beaufort specimens, however, the tentacles of both series are unmarked by lines, spots or annulations. 

 The disc is yellow with white lines crossing it radially." Me. Murrich (1890, p. 135). 



Exterior aspect. The body shews the typical Cerianthid structure and is provided with an 

 aboral pore. When contracted the column has plain longitudinal furrows. 



The tentacles are large and very long. The arrangement is the typical one. In a specimen 

 with 98 marginal tentacles and the same number of labial ones, the arrangement was as follows. 



49 MT .... i, 3, 2, 4 j i, 3, 2, 4 i, 3, 2, 4 ' i, 3, 2, 4 

 49 LT .... 2, i, 3, 4 2, i, 3, 4 i 2, i, 3, 4 2, i, 3, 4 



, 3, 2, 4 1 i, 3. 4, 2, 4, 3 





2,3.2,4 3, i. 4, 2, 4, i, 3 



4, 2, 3, i 

 4, 2, 3, 2 



4, 2, 3, i 4, 2, 3, i 4, 2, 3, i ' 48 MT 

 4, 3, i, 2 i 4, 3, i, 2 4, 3, i, 2 S .... 48 



Whilst the arrangement of the labial tentacles in 4 cycles was very clear, the distinction 

 between the marginal tentacles of the 3rd and 4th cycles was very hard to see. Possibly it might be 

 more correct to distinguish only 3 cycles of marginal tentacles, a question that cannot be answered 

 however with full confidence save by examination of fully extended specimens. Another specimen 

 shewed the following arrangement. 



Marginal tentacles 91 45 M. T. Dt 45 M. T. 



Labial tentacles 89 44 L,. T. Dt. 44 L. T. 



The stomatodaeum is very long. But its relative length to the column is hard to determine 

 in consequence of the great contraction not only of the column but of the stomatodaeum in particular. 

 The stomatodaeum is furrowed longitudinally. In the most aboral portion, these furrows as in 

 the Cerianthidae in general get distinctly deeper. The siphonoglyph which begins immediately beneath 

 the labial tentacles is small in comparison with the size of the animal, as only 4 mesenteries are 

 attached to it. The hyposulcus is not developed, whereas filament-like hemisulci are found well 

 developed. 



Anatomical description. 



The anatomy of this species has been already described by Me. Murrich both in an earlier 

 work of the year 1890, and also recently (1910). In various points however Me. Murrich's investi- 

 gations require supplementing. This is specially the case with the mesenterial filaments and their 

 structure. As appears from the description given below my observations do not always accord with 

 this investigator's. As the structure of column, tentacles and oral disc agree with those of other 

 Cerianthidae, I do not treat these organs in much detail. 



The ectoderm of the column contains very numerous nematocysts with coiled spiral thread 

 (length up to yo/y). In the ectoderm of the marginal tentacles are found numerous thick-walled 

 nematocysts (length 2631 //) whilst spirocysts are more rarely met with. The converse is the case in 

 the ectoderm of the labial tentacles. Here the spirocysts are very numerous, whilst the thick-walled 

 nematocysts are fewer and smaller than in the marginal tentacles (length 19 /LI). 



The stomatodaeum is constructed as in other Ceriantharia. The ectodermal ridges in the 

 upper part are very prominent and contain, besides gland cells, thick-walled nematocysts, that attain 

 a length of 31 36^. If spirocysts occur here, they are very rare. The furrows between the ectodermal 

 ridges are lined with a not very thick ectoderm, which contains, besides supporting cells, no small 

 number of gland cells. The longitudinal musculature of the stomatodaeum is well developed. The 



