2 THE NAUTILUS. 



of aperture and canal 22.5, of body-whorl 29.5 mm.; max. diam. 

 18 mm. Divergence 48°. This specimen was dead when collected. 



University of California Marine Biological Laboratory, stations 

 55 and 67, off San Diego, 25 to 30 fathoms, sand and mud, bottom 

 temperature 50° F. Also dead specimens from stations 21 and 28, 

 Catalina Island, 30 to 40 fathoms, sand and mud, bottom temp. 51° F. 



P. (Genota) stearnsiuna is at once separable fi-om the forty or more 

 specimens of its nearest ally, P. carpenteriana, examined by the 

 writer. The former species is very uniform, although found in dif- 

 ferent localities. With the same number of whorls it is half as large 

 as P. carpenteriana and is proportionately broader. The average 

 ratio of length to diameter is 2.38 in five specimens of P. stearnsiana^ 

 in five specimens of P. carpenteriana it is 2.70. The spire is pro- 

 portionately sliorler in the former' species and the brown bands are 

 more conspicuous. P. carpenteriana 1ms been found in the California 

 Pliocene and Pleistocene and seems to be the first in time of a closely 

 related group, embracing besides the two species already named, P. 

 tryoniana Gabb, Pleistocene and Kecent, and P. cooperi Arnold, 

 found thus far in the Pleistocene of San Pedro only. It gives me 

 great pleasure to dedicate the preseut species to Dr. Kobert Y>. C. 

 Stearns, known to all students of West American conchology. 

 Section Antiplanes Dall. 

 Pleurotoma {Antiplanes) catalinae, new species. 



Shell sinistral, thin, elongated, slendei-, whorls ten to eleven ; 

 color ligiit, pinkish brown, without bands, interior of a[)erture a 

 little lighter: upper whorls more or less chalky; nucleus smooth, in- 

 flated: later whorls convex, suture deeply impressed; sculptured by 

 fine incremental lines and on the last whorls a few obscure, spiral 

 striations, mostly below the periphery; anal fasciole traceable on the 

 spire as a flattened or obscurely grooved band ; aperture narrow ; 

 canal wide and short ; pillar nearly straight, with a well-defined 

 callus, obli(juely truncate below; outer lip produced, deeply emargin- 

 ate near the sutural margin of the whorl. Long, of shell 27, of 

 Mperture and canal 10.5; max. diam. 7.fi mm. Divei-gence 20°. 

 Dredged in 125 fathoms, green mud, off Catalina Island, living, U. 

 C. M. B. L. Station 30 ; off Point Lonia, San Diego, 50 fatiioms, 

 Station 72 (a single, dead specimen); off Point Loma, 106 fatiioms, 

 green mud and sand, bottom tem{)erature 47.9° F., Station 73. 



