CLASS GASTROPODA 
227 
Odostomia orcutti Bartsch, 1917 
Plate 67, fig. 8 
Proceedings of the United States National Museum, 52:667; PI. 46, fig. 8. 
Shell minute, pupoid, pale-brown, marked by retractively slanting, in¬ 
cremental lines only. Nuclear whorls deeply immersed in the first of the 
succeeding turns. Post-nuclear whorls slightly rounded and appressed at 
the summit, the summit of the last one dropping some little distance 
below the periphery of the preceding whorl gives to the penultimate whorl 
an overhanging aspect. Suture moderately impressed. Periphery of the 
last whorl slightly inflated. Base moderately long, strongly rounded, with 
a narrow umbilical chink. Aperture oval; outer lip thin; inner lip slightly 
curved, strongly reflected, and provided with a very strong, oblique fold 
a little anterior to its insertion; parietal wall covered with a moderately 
thin callus. Length, 1.5; diameter, 0.8 mm. (Bartsch.) 
Type in United States National Museum, No. 274006. Type locality, 
foot of Broadway, San Diego, California. 
Range. Known only from type locality. 
Family PTEROTRACHEIDAE 
Genus CARDIAPODA Orbigny, 1836 
Shell minute, cartilaginous; peristome expanded and bilobed in front, 
enveloping the spire behind. (Tryon, Structural and Systematic Con- 
chology .) 
Type. Cardiapoda placenta Lesson. 
Distribution. Atlantic, and North Pacific. 
Cardiapoda placenta Lesson, 1830 
Voyage de la “Coquille,” Zoologie, 253; PI. 3, figs. 2g, 2n. 
Cette petite firole, longue au plus de 2 pounces, est remarquable par 
diverses particularites de formes qui l’isolent de toutes les especes connues. 
La tete est renflee, conique, terminee en avant par une bouche large et 
arrondie, et separee du corps par un leger etranglement. Les yeux sont 
triangulaires, rapproches, tres-noirs, portes sur deux renflements du corps 
en devant. La nageoire dorsale est haute, a bord convexe, mince. Le corps 
se termine en une sorte de queue cylindrique, sans separation marquee 
d’avec le tronc. A sa base un appendice cylindrique, allonge, diminuant 
graduellement de grosseur, se termine par un nucleus discoide, elargi, peu 
epais, colore en noir mat et borde par les branchies qui Tentourent en une 
[ 525 ] 
