176 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. f.S. 



suture anterior to the summit, and a second one of about the same 

 width an equal distance posterior to the suture ; a third brown band, 

 a little wider than these encircles the base almost at its middle. 

 Nuclear whorls two, well rounded, marked by minute pits, which are 

 arranged in axial and spiral series. Postnuclear wdiorls only mod- 

 erately rounded, almost appressed at the summit, marked by slendei 

 incremental lines and fine incised spiral striations. Suture feebly 

 impressed. Periphery of the last whorl strongly rounded. Base 

 moderately long, well rounded. Aperture almost subcircular; outer 

 lip thin at the edge, decidedly curved; inner lip strongly curved, 

 appressed to the base for its greater length, the extreme anterior 

 portion only being free; parietal wall covered by a moderately thick 

 callus, which renders the peritreme complete ; the summit of the last 

 whorl falls considerably below the periphery at the aperture. 



The specimen described and figured is Cat. No. 15423, U.S.N.M., 

 and comes from Guacomayo, Mexico. It has 5.1 whorls and meas- 

 ures — altitude, 2.1 mm. ; diameter, 1.2 mm. 



Cat. No. 264996, U.S.N.M.; 2 from Agua Verde Bay, Gulf of Cali- 

 fornia. 



EXPLANATION OF PLATES. 



Plate 12. 



Fig. 1. Rissoella tumcns (Carpenter), type. 



2. Rissoella hifasciata (Carpenter), type. 



3. Rissoella excolpa, new species, type. 



4. Syncera eompacta (Carpenter), type. 



5. Syncera magdalenensis, new species, type. 



6. Barlecia alderi (Carpenter), type. 



7. Syncera translucens (Carpenter), type. 

 S. Syncera panamensis, new species, type. 

 9. Rissoella anguliferens (deFolin), type. 



Plate 13. 



Fig. 1. Barleeia Jialiotiphila Carpenter, type. 



2. Barleeia bentleyi, new species, type. 



3. Barleeia sanjuanensis, new species, type. 



4. Barleeia carpenteri, new species, type. 



5. Barleeia coronadoensis, new species, type. 



6. Barleeia polychroma (deFolin), type. 



7. Barleeia californi-ca, new species, type. 



8. Barleeia orcutti, new species, type. 



9. Barleeia oldroydi, new species, type. 



10. Barleeia dalli, new species, type. 



11. Barleeia subtemiis Carpenter, type. 



