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the aboral pole. Below the margin about 1.25 cm. there is a marked constriction, above which 

 are a number of distinct longitudinal furrows extending to the margin and giving the upper 

 part of the column a distinctly striated appearance. Elsewhere the column is smooth, except 

 for irregular wrinkles, evidently due to contraction. 



The marginal tentacles were numerous, numbering considerably over one hundred, and 

 were apparently arranged in three cycles. They were almost half the length of the column and 

 were for the most part strong, stout struetures, tapering rather suddenly toward the tips, although 

 many were slender throughout so that they might well be described as filiform. The labial 

 tentacles were also numerous, probably the same number as the marginals, but were more 

 slender and much shorter, hardly projecting beyond the margin of the concave disk. The dense 

 crowding of the tentacles and the poor state of preservation prevented a determination of the 

 arrangement of either the marginal or the labial set, nor was it possible to determine the 

 presence or absence of the unpaired labial tentacle. 



Dim en si ons. — Length of the column, 11 cm.; greatest diameter, 3.5 cm. Length 

 of the marginal tentacles, about 5 cm.; diameter just above their insertion 3.5 — 4.0 mm. Length 

 of the labial tentacles, about 2.0 cm.; diameter just above their insertion 1.0 — 1.5 mm. 



Colour. — The column is throughout its entire extent of the usual dark purple-brown 

 colour; the marginal tentacles were of a light chocolate colour towards their tips, becoming paler 

 proximally. The labial tentacles and the disk and stomatodaeum were coloured similarly to the 

 marginal tentacles, the siphonoglyph, however, being colourless. 



Structure. The stomatodaeum is short throughout the greater portion of its extent, 



measuring only 7 mm. in breadth at a point about 1 cm. distant from the siphonoglyph. The 

 latter structure, however is prolonged downwards for a distance of 2 cm. and is very well markecl. 



The column wall is thick and the mesogloeal processes which support the ectodermal 

 muscle fibres are well developed and closely set. The ectodermal musculature of the disk and 

 marginal tentacles is also well developed that of the labial tentacles, however, being feeble, 

 consisting of little more than a single crenated layer of muscle fibres, the mesogloeal processes 

 being hardly developed. 



The state of preservation was too poor to allow of any study of the histological 

 peculiarities of the various parts, nor was it possible to determine by dissection the arrangement 

 of the mesenteries, the disintegrated endoderm matting them together so that they could not be 

 separated. This much, however could be determined, that a considerable number of mesenteries 

 extended to within 2 cm. of the aboral pole of the body, and that a single couple, which I 

 take to be the second couple of protocnemes, extended still further down, reaching the aboral 

 pole. By taking transverse sections at different levels of a strip of the column whose breadth, 

 starting at the mid-ventral line, amounted to about one-eighth of the entire circumference, it 

 was possible to determine the general arrangement of the mesenteries with approximate accuracy. 

 All the mesenteries in this strip, the directive included, this being readily recognizable by the 

 greater thickness of its mesogloea, extended to a distance of almost 3 cm. below the lower 

 border of the stomatodaeum; below this level the directive and each alternate mesentery lateral 

 to it had disappeared, the remaining mesenteries, as stated above, continuing downward to 



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