CLASS GASTROPODA 
85 
of overhanging appearance; aperture short and rather narrow; outer lip 
sharp, simple, produced; anal sulcus narrow and rather deep, situated just 
behind the posterior channel; body without callus; canal short, wide, 
recurved; pillar lip arcuate, smooth. Height of shell, 19; of last whorl, 
10; of aperture, 6.5; max. diam., 6.5 mm. (Dali.) 
Type in United States National Museum, No. 110609. Type locality, 
Station 2931, off Los Coronado Islands. 
Range. Off Coronado Islands, Mexico. 
This was described as Turns diaulax by Dali. 
Antiplanes briseis Dali, 1919 
Proceedings of the United States National Museum, 56:35; PI. 22, fig. 1. 
Shell elongate, acute, white, covered with a very pale olivaceous 
periostracum, with a blunt, swollen nucleus of about a whorl and a half 
(eroded) and eight subsequent rather flattish whorls; suture obscure, 
appressed; spiral sculpture of one or two feeble flattish cords between the 
periphery and the succeeding suture on the spire, and on the last whorl 
about twice as many more or less obsolete; axial sculpture of rather 
prominent, deeply arcuate incremental lines; anal fasciole wide, not im¬ 
pressed, the deepest part of the sulcus near the periphery; aperture narrow, 
outer lip thin, sharp, much produced; inner lip and pillar erased, the latter 
short, straight, obliquely attenuated in front; canal distinct, produced, 
straight. Height of shell, 18; of last whorl, 10; diameter, 5 mm. (Dali.) 
Type in United States National Museum, No. 212329. Type locality, 
Station off Drake’s Bay, California, in 30 fathoms. 
Range. Drake’s Bay, Coronado Islands. 
Antiplanes thalaea Dali, 1902 
Plate 6, fig. 3; Plate 3, fig. 8 
Proceedings of the United States National Museum, 24:514; 56: PI. 11, fig. 6. 
Shell solid, heavy, with an elongated spire constricted at the sutures, 
and eight or more whorls; nucleus eroded; surface covered with a pale 
apple-green periostracum, which fades in time to a greenish-gray; surface 
sculptured only by incremental lines, faint spiral lines, a slight depression 
of the anal fasciole, and irregular, feeble, broken, short, elevated lines 
which are scattered over the surface and usually directed at right angles 
to the incremental lines; aperture short and narrow, with a short and wide 
canal; outer lip with a deep anal sinuosity, leaving a slightly depressed 
fasciole behind it; anterior part of the outer lip much produced and 
[851 
