458 ETHALIA. 



narrow chink, or even entirely, in some species. < See pi. 57, figs, 

 41, 42, E. guamense, the type species.) 



P. P. Carpenter, A. Adams (since 1860), Dr. W. H. Dall and 

 other recent authors have adopted Ethalia for a group of minute, 

 glassy or porcelaneous white shells, allied to Teinostoma, Leucor- 

 hynchia, Pseudorotella, etc. These, I contend, are entirely distinct 

 from the type species of Ethalia and should be included under 

 Teinostoma or some of its sections. No great violence would re- 

 sult from enlarging Fischer's PSEUDOROTELLA to cover the West 

 American and Gulf species referred by authors to Ethalia. In fact, 

 after a comparison of specimens, I am unable to see any character 

 of importance separating them, part of the so-called ' Ethalia ' being 

 imperforate. I have appended a list of species referred erroneously 

 to Ethalia, and have figured part of them. For further information 

 see Mr. Tryon's monograph of Teinostoma, etc., MANUAL, vol. X> 

 p. 103. 



E. GUAMENSE Quoy et Gaimard. PI. 59, figs. 38, 39. PI. 57, 



figs. 41, 42. 



Shell depressed, perforate, solid, strong, smooth, polished, whitish, 

 mottled and lineolate above with brown, reddish, fawn-color or 

 purplish, with 4 narrow spiral articulated lines, sometimes scarcely 

 visible because of the variegated coloration ; base lighter ; whorls 0, 

 convex, the last rounded, convex beneath ; suture impressed ; 

 aperture oblique, outer wall moderately thick, columella strong and 

 thick, arcuate above, spread upon the body-whorl and nearly over 

 the umbilicus in a pad of callus, which is either white, pink or deep 

 crimson ; callus kidney-shaped, but slightly convex, filling the um- 

 bilicus except a narrow chink ; from the outer termination of the 

 callus an arcuate groove extends to the base of the columella, within 

 which the surface of the shell is radiately finely striate and darker 

 colored. Alt. 13, diam. 18 mill. 



Guam ; Luzon, Philippines (Soivb.)* 



Rotella guamensis Q. & G., Voy. de 1' Astrolabe, Zool. iii, p. 267, 

 t. 61, f. 32, 33, 1834. KIENER, Spec, et Icon. Coq. Viv., p. 7, t, 2, 

 f. 2. SOWERBY, Thes. Conch, v, p. 137, f. 28, 29 ; in Conch. Icon., 

 f. 18 Umbonium (Ethalia) guamense A. AD. P. Z. S. 1853, p. 189. 

 Trochus callosvs, KOCH, in PHILIPPI, Abbild. i, Trochus, t. 4, f. 2, 

 p. 138, June, 1844. Conchylieii Cab., p. 233, t. 35, f. 7. FISCHER, 

 Journ. de Conchyl. 1878, p. 207 ; Coq. Viv., p. 378, t. 115, f. 3. 

 Rotella montrouzieri SOUVERBIE, Journ. de Conchyl. 1860, p. 123, t. 



