ARNOLD — THE PALEONTOLOGY AND STRATIGRAPHY OP SAN PEDKO. 271 



portion <>t the whorls, but fuse anteriorly before reaching suture; the ribs are bent sHghtly forward 

 near their posterior extremity; intercostal sjiaces deep, narrow; spiral sculpture fine but conspicu- 

 ous; the sutures are deeply impressed, with smooth sides, caused by the fusion of the ribs before 

 leachiiij; the sutures; body-whorl rounded, smooth below, except for minute incremental lines and 

 spiral ornamentation. A|)erture subquadrate; the outer lip joins the straight, somewhat revolute 

 colunulla at a right angle. 



/h'DUJisions. — Long. 5 mm ; lat. i.i mm.; altitude of body-whorl 1.4 mm. 



This species soinewliat icsciulilcs T. stcnrndl, hut is distiiigiii.shahle from that 

 species hy tlie less mimhcr and ,-;rfaler pi-oiiiliniico <»!' tiie rihs, wiiicli in some cases 

 heiul slii^htly forwaixl near tiieir posterior extremity. 7'. simi/is was i{hMitifiO(l hy 

 Dr. Dall; hut the species was omitted from the text prepared hy Dall and Bartscli. 



Rare in the lower 8aii Pedro series at Deadman Island and San Pedro; 

 cnniniiiii in the upper San Pedro series at San Pedro and Los Cerritos. 



Livinfj. — Gulf of ( alit'ornia to Panama (Carpenter). 



Pleistocene. — San Pedro (Arnold). 



286. Turbonilla (Strioturbonilla) stearnsii D. <t- B., sp. nov. 



I'l.ATK II, Fli;S. 5 AND Ott. 



Shell milk-white, rather stout; nuclear whorls two, small, helicoid, their a.xis being at right 

 angles to the axis of the post-nuclear whorls; post-nuclear whorls very slightly convex, almost 

 flattened, somewhat contracted at the base, and strongly shouldered at the summit, traversed by 

 eighteen to twenty-six oblique, flexuose, axial ribs, which render the summits of the whorls wavy; 

 intercostal spaces deep, terminating a little above the periphery, thus leaving a narrow, plain band 

 above the suture, as in T. iorqiiata siylina; the entire surface of the whorls is marked by numerous 

 faint, wavy, spiral striations, which also ornament the otherwise plain basal portion of the last whorl; 

 suture well defined, slightly channeled; aperture subovate, anterior angle obtuse; outer lip thin, 

 joining the short, somewhat revolute columella in a gentle curve. 



Dimensions. -^J.onfr. 9.2 mm.; diam. 2.3 mm. 



The type, which has eleven and one-half post-nuclear whorls, is from the post- 

 Pliocene of San Diego. . 



This species in a general way resemhles 7\ forquafn dijUud, l)iit differs from it 

 in heing nuieh more rohiist, of greater diameter tlirotighoiit, and in having the fine, 

 wavy scidptnre characteristic of the section. 



Tavhon'illa f StrioturbonUlnJ siearut>ii occurs quite ahundantly in the po.st- 

 Pliocene deposits at San Diego and San Pedro. It also occurs recent in the Gulf of 

 Califoiiiia. Tln' name is proposed in honor of Dr. R. E. C. Stearns of Los Angeles, 

 who collected many specimens of this group. 



287. Turbonilla (Strioturbonilla) torquata Gould. 



P1.ATK II, Fics. 4 A.N'ii 4a. 



Che>nnil:ia torquata Gld., Bost. Jour. Nat. Hist., Vol. IV, 1853, p. 384, PI. XIV, fig. 16. 



Shell slender, solid, milk-white, entire surface marked by faint, wavy, spiral striations; 

 nuclear whorls three, helicoid, their axis being at right angles to and to one side of the post-nuclear 



