THE ANNALS 
AND 
MAGAZINE OF NATURAL HISTORY. 
[FIFTH SERIES. ] 
No. 59. NOVEMBER 1882. 
XXXIV.—Preliminary Notice of Cephalodiscus, a new Type 
allied to Prof. Allman’s Rhabdopleura, dredged in H.M.S. 
“ Challenger.’ By Prof. M‘Inrosu, F.R.S.* 
[Published by permission of the Lords Commissioners of the Treasury. ] 
A sHorT time ago Mr. Murray, Director of the ‘ Challenger ’- 
Expedition Commission, drew my attention to an anomalous 
organism which had been relegated to the Annelida; and 
though on examination it proved to be an ally of Rhabdo- 
pleura, Prof. Allman and Prof. Busk (both of whom had 
arrived at the same conclusion in regard to its systematic 
position) most kindly and_disinterestedly insisted on my 
describing it, especially as Phoronis had just been the subject 
of investigation. 
This remarkable form was dredged at Station 311 (in the 
Strait of Magellan {), January 11, 1876, in lat. 52° 50’ S., long. 
* Communicated by the Author, having been read (with accompany- 
ing drawings) at the Southampton meeting of the British Association, 
August 1882, 
+ The Strait of Magellan appears to harbour several molluscoid rari- 
ties, Thus the remarkable Goodsiria coccinea of Prof. R, O. Cunning- 
ham (Trans, Linn. Soe. vol. xxvii. p. 489, tab. 58. fig. 3) is a social Asci- 
dian with an elongate (above 2 feet) lobed, rooted, fibro-gelatinous mass 
of a vivid scarlet colour, “ reminding one in some measure of the fleshier 
Aleyonoid polyps,” in which minute flask-shaped animals are imbedded in 
circumferential cells, The animals are about a line in length, and, so far 
as can be made out from the sketches, appear to be social Ascidians. 
From the same neighbourhood the curious Pyura Moline of Blainville 
also comes. 
Ann. & Mag. N. Hist. Ser. 5. Vol. x. 23° 
