MOLLUSCA.—HEDLEY. 
57 
spirals, of which five central ones are prominent and widely spaced ; on the snout are 
three low and faint ones. The penultimate has live such spirals, one bordering the 
suture. Aperture pyriform, outer lip thin and simple, canal short, open, columella 
excavate at the inner lip. Length, 13-5 ; breadth, 4-3mm. 
This species is named in honour of Mr. C. T. Madigan, who led an important 
exploring expedition from the Western Base. 
Four specimens taken, July 4th, 1912, from 25 fathoms ; and six, December 14th, 
1913, from 45-50 fathoms, Commonwealth Bay, Adelie Land. 
Prosipho mundus Smith. 
var. macleani var. nov. 
(Plate VIII., fig. 94.) 
Prosipho mundus Smith, “ Terra Nova ” Exped., Zook, ii., Moll., 1915, p. 70, pi. i., fig. 10. 
Before Mr. Smith’s account of the “ Terra Nova ” mollusca reached me, I had 
prepared the following description as of a new species. My shell answers generally to 
P. mundus, but has the radial sculpture much fainter. It seems, therefore, proper to 
present the account prepared for a variety. 
Shell ovate-lanceolate. Colour uniform pale buff. Whorls six, of which the upper 
two are smooth, rather elongate protoconch. Sculpture: the last whorl carries 13 
spirals, a small one on the shoulder is followed by six median which are large and spaced, 
the rest diminish progressively tow T ards the snout. The penultimate whorl has four 
prominent median, and one small subsutural keel. On the upper whorls are incipient 
radial ribs, and in the interstices of the cinguli of the lower whorls are fine radial striae. 
Length, 8*5 ; breadth, 4mm. 
Named in honour of Dr. A. L. Maclean, Medical Officer of the Expedition. 
Four specimens taken, July 4th, 1912, from 25 fathoms, Commonwealth Bay, 
Adelie Land. 
Prosipho spiralis Thiele. 
Prosipho spiralis Thiele, Deutsch. Siidpol. Exped., xiii., 1912, p. 209, pi. xiii., fig. 2. 
One specimen, December 22nd, 1913, from 350-400 fathoms, in Commonwealth 
Bay, Adelie Land. 
Vol. IV., Part 1—h 
