80 



brilliant orange color; this orange-colored rib is also exteriorly 

 bounded by a shallow furrow which becomes obsolete toward the 

 aperture. The base of the shell otherwise exhibits faint revolving 

 sculpture. Dimensions: Altitude, 36 mm., diameter maximum, 34 

 mm. The above combines the sculptural features of the Japanese 

 Chlorostomas and West Mexican U vanillas, more particularly U. 

 olivacea. It is a much handsomer shell than the latter and the 

 most northerly form of the group yet detected on the west coast." 

 — Stearns, Nautilus 6 : 85-8G. Guadaloupe Island. 



YOLDIA MONTEREY ENSIS. 



"Shell large, stout, inflated, with a polished, dark greenish 

 olive epidermis; beaks eroded in all the specimens, situated in the 

 anterior part of the middle third of the shell, not prominent;, 

 valves full and rounded, anterior end evenly rounded into the up- 

 per and basal margins; posterior end narrower, rounded, the ex- 

 treme end nearer the cardinal margin with which it almost forms 

 an angle, below sloping obliquely toward the basal margin, with a 

 very obscure broad ray impressed in a radiating manner from the 

 beaks toward the oblique slope, the profile of which it does not 

 perceptibly indent; surface sculptured only by feeble incremental 

 lines; epidermis polished with one or two darker concentric color 

 zones and a microscopic, irregular, radially disposed wrinkling, 

 most conspicuous at the margins of the impressed ray; posterior 

 cardinal margin nearly straight, anterior ditto evenly rounded; in- 

 terior porcellanous white, the pallia I sinus not reaching the middle 

 vertical line of the shell, broad and rather rounded; ligamental 

 fosset large, cuplike; anterior teeth V-shaped, about 22 in number, 

 strong and prominent; posterior teeth similar, and forming an e- 

 qually long line but only 18 in number, the posterior cardinal 

 margin showing a long narrow impressed area very feebly marked; 

 length of shell 32; beak from anterior end 12; vertical from beak 

 to base 17; max. diameter 13 mm. Habitat U. S. Fish Com. sta- 

 tion 3202, in 382 fathoms green mud, Monterey bay, California, 

 bottom temperature, 41 deg. Fahrenheit. This fine shell recalls 

 Y. thraciceformis, but is smaller, without the angularity of that 

 species and proportionately more solid. It was dredged by the 



U. S. Ste imer Albatross, several years ago. It is probably a deep 

 water species exclusively at least in the latitude of California. The 

 types are in the IT. S. Nat. Museum, 106,972."— Dall Nautilus 7: 

 29-30. Jl 1893. 



