DESCRIPTION OF A SPECIES OF ACTABO:Nr FROM THE 

 (QUATERNARY BLUFFS AT SPANISH BIGHT, SAN DIEGO, 

 CALIFORNIA. 



By Robert E. C. Stearns. 



/Jotiorary Asiiociate in Zoology. 



At Spnnisli Bight, San Diego, a fine exposure of Quaternary marl 



occurs, containing well preserved fossils, most of which are recent 



species. Among them some forms have been discovered which appeared 



to be new, but which have, later, turned up also in the recent fauna of 



this part of the coast. One of these is the following line species of 



Actacon.^ 



ACTAEON TRASKII Stearns. 



Shell small, conical above, cylindrical, rather solid, opaque, somewhat 

 glossy; sculptnre consisting of numerous tine spiral impressed lines or 

 grooves, which become wider toward the base of the body whorl, mak- 

 ing the sculpture of the lower i)ortion of the shell Urate; part of the 

 lirae are slightly grooved and in some cases show a tendency to run in 

 pairs; the grooved lini's are not quite regular in their relative dis- 

 tances, and some are deeper than others; the surface is otherwise sculp- 

 tured by shari), close-set, incremental lines; these latter are subordinate 

 to the si)iral sculpture an<l are more consincuous on the lower part of 

 the body whorl. Color dull-cream white, with (in the examjde before 

 me) two obscure, broad, pale rufous bands on the body whorl. Spire 

 short, obtusely conical. Whorls, six (probably, apex in example some- 

 what eroded); suture distinct, narrowly channeled. Aperture about 

 two thirds the length of the shell (not quite 9mm,), acutely angnlar 

 above, rounded and etiuse below, finely Urate and glossy within, with a 

 thin glazing on the body whorl. Outer lij) thin, simple. Columella 

 short and flexuous, with a conspicuous fold, curving around the same 

 and thickening the edge of the lip, whi(;h is moderately produced in the 



umbilical region. 



A2 B 



mm. mm. 



Lenjrfhof shell. U 24 



Lfiigthof body whorl i» 19 



Breadth C 12 



' Preliminary desfription in The Nautilus, June, 1897, XT, p. 14. 



"A, Hainliu's specimen; I>, Type in U. S. National Museum, Reg. No. 148241. 



Proceedings U. S. National Museum, Vol. XXI— No. 1145. 



