54 Prof. M'Coy on a new Volute. 



noid process. The symphysis extends 3 inches 6 lines ; and the 

 teeth-series occupies nearly one-half of the upper margin 

 from the tip to the coronoid process, measuring 9 inches 4 lines 

 in length, and the free part of the margin to the extremity of 

 the coronoid process 10 inches. 



I know nothing of the other parts of the skeleton. 



On my first voyage across the Atlantic, I saw seven Olohio- 

 cephali swimming near the vessel, in 10° N. lat., on the 2nd 

 November, 1850 (see my 'Eeise nach Brasilien,' Berlin, 

 1852, p. 43), and observed them for a long time. I suppose 

 these animals would be of the same species as the one here 

 described ; and if so, their whole external appearance is iden- 

 tical with the figure given by Couch (Ann. Mag. Nat. Hist. 

 1st ser. vol. ix. 1842, pi. 6). But as I did not see the under- 

 side of the swimming animal, I cannot say whether this 

 species has the white spot which is characteristic of the 

 European animal. 



VIII.— 6>;i a new Volute, By Prof. M<CoY. 



[Plate II. fig. 1.] 



Valuta Thatcheri (M'Coy). PI. II. fig. 1. 



Slender, elongate fusiform ; greatest width (which is near 

 the middle of the body-whorl) only half the length of the body- 

 whorl ; about ten tubercles on the penultimate whorl, slightly 

 below the middle; only about seven on the shoulder of the 

 body- whorl, from their being obsolete near the outer lip. Seven 

 thick plaits on the columella, the two posterior smaller than 

 the rest, which are nearly equal. Colour a white ground, with 

 a row of elongate quadrangular spots on the suture and two 

 broad spiral bands of hieroglyphic markings on the body-whorl, 

 one just below the tubercles and the other near the anterior 

 end ; in front of the latter an irregular row of small quadi-ate 

 spots ; all the markings pale yellowish brown ("burnt-sienna " 

 colour) ; traces of a yellowish reticulation between the bands. 



Length of the last three whorls 2 inches 10 lines, width 

 1 inch 1^ line ; length of penultimate and antepenultimate 

 whorls together 6 lines. 



I name this beautiful Volute after Mr. Charles M. Thatcher, 

 of Melbourne, an enthusiastic and acute conchologist, who 

 perceived the probable novelty of the species from the most 

 obvious characters of the slender form and seven plaits to the 

 pillar — a combination of characters separating it from all others 

 I know. Mr. Thatcher has added the specimen to the National- 

 Museum Collection at Melbourne. The spire is broken. 



Habitat unknown. 



