REPORT ON THE ACTINIARIA. 25 



Habitat.— (a) Station 311, Jaimary 11, 187G ; deptli, 245 fathoms. Three siicci- 

 mens. (6) Station 320, February 14, 1876 ; depth, r,00 fatlioms. One .si)ecimen. 



Dimensions. — Length of the contracted animal, 2-5- 3-2 cm. ; breadth, 2-5-3-5. 



At first I was inclined to refer the three specimens from Station 311, which were 

 seated on MoUiiscan shells, and the single specimen from Station 320, to Phellia 

 pectinata ; for they possessed the characteristic appearance of the body-wall, resemblin<r 

 the tunic of Cynthia;, while the ujiper indrawn part of the wall presented the ridged 

 surface which has been already figured. I was, however, persuaded to a closer study 

 by observing some points of divergence in tlie structure of the peripheral region of 

 the body-wall. The transverse and longitudinal ridges are wanting, instead of wliich 

 occur knobs, resembling those of Cereus spinosus ; these start with a broad base, and 

 terminate in a slightly truncated tip ; they are distinguished from the body-wall, which 

 is nearly white, by a brownish tint, and mtiy amount to 200 in number, distributed 

 more abundantly on the upper than on the lower regions of the body-wall. The upper 

 knobs are as much as 0-25 cm. long, and are more strongly developed than the rest; 

 they become gradually smaller below, and finally appear only as fine grains. Such an 

 arrangement of the knobs in series, as exists in Bunodes, does not occur. 



The mesogloea of the body-wall is so extraordinarily stiff as to cause some trouble, 

 before good sections of the sphincter can be elFected. The latter is essentially constituted 

 as in Phellia p>ectinata, so that reference to the description given under that species is 

 sufficient. In position it is considerably nearer to the ectoderm than to the endoderm. 



The oral disc and stomatodaeum are of a brownish violet (partially altered in the 

 alcohol), the former lighter in tint than the latter. On the stomatodfeum the two 

 siphonoglyphes, which are not pigmented, and are consequently of a whitish yellow, 

 strike the eye on opening the animal as two broad, sharply-marked, stripes. They are 

 only distinguished from their surroundings by this difference of colour, since they are 

 flush with the rest of the stomatodseum. They are crossed by transverse folds regularly 

 arranged, which are continuous over the rest of the stomatodseum. Further, the 

 stomatodseal cone is hardly expressed at all, and the longitudinal furrows, which so 

 commonly run parallel to the siphonoglyphes between the mesenterial insertions, are 

 wanting. 



For the characterisation of the species the condition of the musculature of the oral 

 disc is also of importance ; it exhibits two methods of formation. In the one case it is 

 purely ectodermal and markedly pleated, the pleats running parallel to one another, 

 and only slightly arborescent (PI. II. fig. 9). At other points (fig. 8) the arborescence 

 is very considerable, the individual Ijranches anastomosing with one another ; the 

 musculature thus becomes partly mesogloeal, and a very obvious and stout muscle- 

 layer arises. The muscle-fibres are here, as in the sphincter and the powerfully 

 developed laminae of tlie retractors, of exceptional thickness. 



(ZOOL. CHALL. EXP. — PART L.X.XIII. — 1888.) T>(\<U 4 



