Miscellaneous. 207 



75° 12' N. lat., 3° 2' E. long., at a depth of 1200 fathoms, tempe- 

 rature — 1°-6 C, in brown mud. Feeds chiefly upon Diatoms and 

 Foramiuifera, swallowing the fine mud in which these creatures 

 live in extraordinary abundance. The skin is transparent with a 

 whitish tinge, so that in places where it is compressed it appears 

 quite white. The five-lobed leaf of the tentacles, especially the part 

 fringed with spicules, is deep orange-yellow. Buccal disk orange- 

 yellow, with a darker, nearly brown ring round the mouth. 



Myriotroclms Rinkii, Steenstrup*. 



This species- has been described under the same name by Liitkenf, 

 StimpsonJ, 8elenka§, and Semper|| ; but Theel's Myriotroclms 

 Einhii, from Nova Zembla^, is regarded by MM. Keren and 

 Danielssen as identical with Chirodota brevis, Huxley **, of which 

 OUgotrochus vitrev^, M. Sarsff, is also a synonym. 



ACANTHOTKOCHUS, g. n. 



Body cylindrical, apodal, rounded at the posterior extremity. 

 Sexes separate ; no intestinal appendages (organs of respiration). 

 Skin furnished with two kinds of differently formed calcareous 

 wheels. The one kind has winged radii, and teeth issuing from 

 the inner margin of the periphery ; the other kind of wheel is more 

 than twice as large, and has also winged radii ; but from the outer 

 margin of the periphery there spring long teeth turned inwards. 

 Twelve digitate tentacles, which can be concealed in the body. 



AcantJiotrochus mirabilis, sp. n. 



Body 10-12 miUims. long, cylindrical, widened and rounded off 

 at the hinder extremity. Mouth and anal aperture central. Skin 

 transparent, beset throughout with two different kinds of wheels. 

 Those of one kind are stalked, small, furnished usually with eleven 

 radii, and from the inner margin of the periphery spring generally 

 two triangular teeth between each two radii. The larger wheels 

 have usually 8-11 radii ; and from the outer margin of the peri- 

 phery spring long pointed teeth, equal in number to the radii. 

 Twelve tentacles, furnished with three divided digitate leaves. Five 

 longitudinal muscles. Skin in the living animal perfectly trans- 

 parent, with fine glistening points, which under the lens are found 

 to be calcareous wheels. The margins of the tentacles brownish. 



Hab. Station 283, 73° 47' N. lat., 14° 21' E. long., in 767 

 fathoms, temperature —1°'4 C, 5i7ocMZmrt-ooze; Station 295 (see 

 Kolga hijaUna) ; Station 312, 74° 54' N. lat., 14° 53' E. long., in 

 658 fathoms, temperature ^1°*2 C, brown and green mud. 



* Vidensk. Meddel. naturh. Foren. Kjob. 1851, pp. 55-60. 



t Ibid. 1857, p. 21. 



X Synopsis Marine Invert. Arct. Exp., Proc. Acad. Nat. Sci. Phil. 1863, 

 p. 138. 



§ Zeitschr. f. wiss. Zool. xvii. (1867) p. 367. 



II Reisen im Arcbip. der Phil., Holothuria, i. p. 24 (1867). 



% Appendix to Sutherland's * Journal of a Voyage to Baffin's Bay,' &c 

 vol. ii. p. 221 (1852). 



** Note sur quelques Holothuries des Mers de la Nouvelle Zemble 

 (Upsal, 1877). 



tt Vidensk. Selsk. Forhandl. 1865, p. 200, and in ' Fauna littoralis Nor- 

 vegise,' Heft 3, p. 49. 



