44 
THE VOYAGE OF H.M.S. CHALLENGER. 
2. Kinetoskias arborescens, Daniellsen. 
Kinetoskias arborescens, K. and D. 
Bugula umbella, Smitt. 
3. Kinetoskias cyathus, Wyv. Thoms, (sp.) 
Naresia cyatlius, Wyv. Thoms. 
1 Kinetoskias smittii, K. and D. 
4. Kinetoskias pocillum, Busk. 
Of the above, two have come under my observation from the Challenger collection, 
viz. : — Kinetoskias cyathus , Wyv. Thoms., and Kinetoskias pocillum, Busk. 1 
(1) Kinetoskias cyathus, Wyv. Thoms, (sp.) (PL VIII. fig. 1). 
Naresia cyathus, Wyv. Thoms., Voyage of the Challenger, The Atlantic, vol. i. p. 142, 1877. 
Character. — Zooecia about 0"'045 by 0"'02 ; oblong, the outer border somewhat 
hollowed, and towards the lower part presenting a sort of step on which the avicularium 
is articulated, and furnished with a special muscle (PI. VIII. fig. la). Aperture entire, 
or very nearly so. The upper and inner angle rounded off, and the external produced 
into a short pointed conical process. Posteriorly the zooecium (fig. lb) is very convex, and 
the surface perfectly smooth. The outline is much the same as in front ; the outer border 
is acute, and the inner rounded. Ocecia of large size, attached to the middle of the sum- 
mit of the zooecium in front, and projecting forwards in the form of a wide shallow hood. 
Avicularia about 0"‘02 long, by 0"‘006 wide, the mandible measuring 0"‘01, and 
being much curved. 
Habitat. — Station VI., lat. 36° 23' N., long. 11° 18' W., 1525 fathoms; Globigerina 
ooze. Station 325, lat. 36° 44' S., long. 46° 16' W., 2650 fathoms; blue mud. 
Messrs. Koren and Daniellsen are inclined to consider that their Kinetoskias smittii 
is identical with Kinetoskias cyathus ; but so far as I am able to judge from their detailed 
description and figures, this can hardly be the case. The form and size of the zooecia, and 
of the avicularia and ooecia, undoubtedly appear to correspond with those of Kinetoskias 
cyathus ; but the general aspect of the zoarium in the two cases is utterly dissimilar. 
In this particular, however, it should be remarked that the natural size figure given 
in their pi. iii. does not at all correspond with the description in the text. But in 
Kinetoskias cyathus there are no transverse rugae on the back of the zooecium, and the avicu- 
larium in Kinetoskias smittii is apparently attached above the middle of the outer border, 
whilst in Kinetoskias cyathus it arises from a distinct step-like process very near the bottom. 
1 In the Quart. Journ. Micr. Sci., N. S., vol. xxi. Jan. 1881, I have given an account of the structure of this very 
remarkable genus, the principal points connected with which had however already been noticed by Messrs. Koren and 
Daniellsen, and by Professor Smitt, who had left very little new to be said on the subject. 
