BULIMULUS. 151 



ing lines; whorls moderately convex, base evenly rounded ; sculpture 

 on the later whorls only of faint incremental lines; umbilicus small 

 and narrow, aperture rather elongate. Alt. of shell 17.5, diam. 8 

 mill. (Dall). 



Galapagos : Hood Island (Snodgrass and Heller). 



Bulimulm approximatus BALL, P. A. N. S. 1900, p. 90, pi. 8, f. 4. 



''A single specimen of this shell was obtained which differs from 

 all the others of the nux group in the absence of spiral sculpture 

 and the smooth and polished surface. The peristome is not quite 

 matured, so it cannot be determined whether it is reflected or not, 

 but the probabilities are in favor of its being simple and unre- 

 flected." 



B. HOODENSIS Dall. PI. 24, fig. 4. 



Shell allied to B. unifasciatus Sby., but smaller, with about six 

 convex, rapidly-tapering whorls ; nucleus sculptured as usual in the 

 group, livid purple ; later whorls smooth, polished, with no sculpture 

 but faint incremental lines; color light yellowish-brown, with two 

 broad reddish-purple spiral bands nearly peripheral, and a narrower 

 one in front of the suture ; base evenly rounded, with a narrow but 

 deep umbilicus ; aperture ovate oblong, the peristome white, thick- 

 ened and distinctly reflected ; pillar broad, white, not swollen, a thin 

 wash of callus over the body, the external coloration distinct within 

 the aperture. Alt. of shell 18, of aperture 8.5, diam. of shell 8.5, of 

 aperture 6 mill. (Dall). 



Galapagos : Hood Island (Snodgrass and Heller.) 



Bulimulm hoodensis DALL, P. A. N. S., 1900, p. 91, pi. 8, f. 1. 



" This well-marked form more nearly resembles some of the con- 

 tinental species than the typical Nsesioti. The distinctly-reflected 

 lip and rapid enlargement of the whorls distinguish it from any other 

 Galapagos species." 



B. JACOBI (Sowerby). Vol. xi, p. 111. 



" This seems to be the commonest and, among the islands, the 

 most generally distributed species of the Galapagos. It was obtained 

 by Messrs. Snodgrass and Heller at James and Albemarle, where it 

 was previously known, and also from Narborough and Abingdon, 

 where it had not previously been reported. There is not a great deal 

 of variation in the specimens, which were found at elevations of from 



