SOUTHERN CALIFORNIA ACADEMY OF SCIENCES. 7/ 



pressed as it gages 20 mm. ; the whorls are strongly rounded ; 

 sutures deeply impressed; body whorl 25 mm. long, much in- 

 flated; outer lip not thickened but has a bulging inflation 

 turning inwards; the edge being entire. The columnella be- 

 ing hid in the matrix but from several fragmentary examples; 

 the columnella is short, twisted ; channel wide ; aperture very 

 wide. 



This shell was found in the same deposit as C. aphelus Dall 

 and C. griseus Dall. 



Geological formation : Pliocenl ; Santa Monica Range. 



Chrysodomus aphelus Dall. 



The U. S. Report on Albatross Mollusca Pro. U. S. Nat. 

 Mus. Vol. XII pages 219-362, gives descriptions by Dr. Healy 

 Dall of various living Mollusks dredged from near Santa 

 Barbara, Cal. 



An examination of the Pliocene strata of the Santa ^lonica 

 Range has brought to light two of Dr. Dalls species and a 

 third one in the same deposit that the dredge of the Albatross 

 did not discover. 



"The living shells, (according to the Albatross Reports) 

 occur in 414 fathoms grey sand." The fossils occur in a silty 

 formation in which remains of marine and terrestrial flora 

 abound. The elevation from sea level of these strata varies 

 from a few feet up to seventy or a hundred feet above.. Phe 

 height or depth of these strata carries no geological value 

 but it is their position and what they contain that yield their 

 natural worth ; these strata dip strongly to the southwest at 

 various angles and in places tilted to the perpendicular. These 

 fossils therefore may have enjoyed at one time a depth of 414 

 fathoms, particularly.' so as the deposits dip under a hundred 

 feet of nearly horizontal Pleistocene. 



Chrysodomus aphelus Dall. (Albatross Mollusca PI. VI. 

 fig. 7.) 



Shell bucciniform ; six whorled, smooth ; nucleus eroded ; 

 whorls full, well rounded ; sutures distinct and somewhat deep ; 

 sculptum of faint incremental lines which curve to the swell- 

 ing of the whorls ; obscure spiral traces ; outer lip thin, smooth, 

 polished white, on the inside, which is reflected rather strongly 

 at the upper angle but diminishes gradually towards the chan- 

 nel; columnella short, not calloused, throat smooth white; pil- 

 lar very obliquely truncate. 



Dimensions : Report gives maximum longitude 32 mm. ; 

 maximum latitude 18 mm. ; but the fossils give increased di- 

 mensions ; the maximum being 40 mm. to 20 respectively. The 

 majority of the fossil forms are however much below these 

 measurements. 



