388 BULLETIN OF THE 



Liotia (Arene) Briareus Dall. 



Plate XXIV. Figs. 5, 5 a. 



Turbo (Liotia?) Briareus Dall, Bull. M. C. Z., IX. p. 52, 1881. 



Habitat. Station 60, off Havana, in 80-480 fms. Station 20, off Bahia 

 Honda, Cuba, in 220 fins., bottom temperature 62°.0 F. Station 166, off 

 Guadelupe, in 150 fms., sand, bottom temperature about 60°.0 F., one living 

 specimen. Station 272, off Barbados, in 76 fms., sand and shell. 



The alcoholic specimen was well preserved. The operculum has been al- 

 ready referred to. Its outer margin is produced into a thin lamina, which 

 persists, and splits radially, giving a hispid appearance to the outside surface 

 of the operculum, which contains about twenty turns. The inner surface is 

 golden brown, very polished, and with a small central knob corresponding to 

 the deep indentation of the outer surface. The muzzle is long and rounded; 

 the tentacles long and slender; the eyes large and black on distinct pedicels. 

 The epipodial fringe shows a moderate lobe of triangular shape just behind 

 the eye, but not extended to the eye peduncle; and there are four well-marked 

 long lateral processes on each side as large as the tentacles, and two more 

 smaller ones peep out from under the edges of the operculum. The foot is 

 rather broad, squarish and simple in front, rounded behind, short. The sides 

 of the foot are yellowish with numerous brown specks; there are some specks 

 of the same kind between the tentacles. Front of the head devoid of lappets 

 or other appendages. With the above exceptions the exposed parts are yellow- 

 ish. There is a single rather narrow gill. The anus forms an elongated 

 papilla. I could find no jaw. The radula is small and short The formula 

 j s 5 -i- 5 + i+5^.?. The rhachidian tooth is like that of Delplrinula ; there 

 are five simple-cusped broad-based laterals, the fourth and fifth larger than 

 the inner ones. There are numerous slender simple uncini with long scythe- 

 shaped cusps. 



The shell of this species is suoject to extraordinary variations. Beside the 

 normal and typical form, figured with erect long channelled spines, there is 

 a variety in which the umbilicus is nearly closed and the spines rather short. 

 These specimens are also of a darker and duller red, and perhaps a little less 

 elevated. 



A still more remarkable variety is destitute of any spines or ridges whatever. 

 The general form is the same, the places of the spiny spiral ridges are marked 

 by the red color and the interspaces by white; yet there is nothing left of the 

 ridges but the color, except on the very early whorls. The surface shagreening 

 is retained. The shell is rose-colored. For the first I would propose the va- 

 rietal name of perforata, and for the second that of aspina. 



This species may be distinguished from L. Bairdii by the sharp wavy sha- 

 greening of its surface and the heavy shelly coat on the operculum, in general 

 also by the larger umbilicus, flatter base and basal sculpture, and by the long, 

 erect, thin trough-like spines. The strong carina or ridge bordering the 



