340 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxx. 



at tJit^ suniinits. oriuinionted with poorly developed, broad, low, almost 

 vertical axial ribs which are strong-est at the summit of the whorls and 

 gradually giow ^\ eaker toward the periphery. The first three post- 

 nuclear whorls pro])a])ly are lost. The second of those left has eighteen 

 lihs: the antii)cnultiniato twenty-four and the penultimate twenty-two; 

 on this they are nuu-li weaker than on the preceding whorls. Inter- 

 costal spaces hroad and shallow, scarcely sunk })elow the general sur- 

 face of the shell, l)ecoming obsolete toward the peripher}^ like the 

 ribs. 8utur(\s well marked. Base of the last whorl rather prolonged, 

 smooth. Aperture moderately large, suboval, posterior angle acute; 

 outer li]) thin, junctit»n of the columella and outer lip well rounded; 

 cohunella oblique, somewhat revolute, provided with a prominent fold, 

 a little anterior to its insertion; parietal wall covered by a thin callus. 

 The sixteen remaining whorls measure: long. 7.8 mm.; diam. 2.1 mm. 

 The type is No. 58111 of the collection of the Philadelphia Academy 

 of Natural Sciences and was collected b}' Garrett, in the Viti Islands. 



TURBONILLA (CHEMNITZIA) CRENULATA Menke. 



Plate XXI, tig. tl. 



(hi/hrnia crcmdala ,Menke, Synopsis Methodica Molhiscoruni, IH'.iO, j). 137. 



Shell elong-ate-conic, subturrited, milk-white. Nuclear whorls 

 decollated. Post-iuiclear wlioils flattened, somewhat shouldered at 

 the summit, crossed by strong, rounded, very obli(jue, slightly sinuous, 

 axial ril)s, of which sixteen occur upon the fourth, twenty upon the 

 tenth, and twenty-Four upon the penultimate whorl. These ribs show 

 a tcMidency towiird fusing at the sununit of the whorl, where they 

 become slightly thii-kened; they extend strongly to the well-impressed 

 sutures. Intercostal spaces about one-half as wide as the ribs, mod- 

 erately depressed, tei'minating suddenly at the somewhat angulated 

 periphery of the last Avhorl. Base of the last whorl short, well 

 rounded, moderately large, marked only by lines of growth. A])er- 

 ture sub(iuadrate, somewhat efluse at the junction of the lip and col- 

 umella. })osterior angle acute, outer lip thin, showing the external 

 sculpture within l)y transmitted light, columella straight, almost ver- 

 tical, somewhat revolute, provided with a very weak oblique fold at 

 its in.siTtion; parietal wall covered by a thin callus. 



There are two specimens in the PaHel collection which we believe to 

 ))e the types. They ar(> labeled "Mexico."''' They agree in every re- 

 spect, except in the number of whoils. We have figured and described 

 the larger one of the two, which has thirteen post-iuiclcar whorls and 

 measures: long. S.O nun; diam. 2 nun. 



.Menke" states that the specimens were collected by Doctor Schiede. 

 Upon s(>arch it was ascertained that Doctor Schiede collected on the 



«Syno])sis .Mt'thoilica Mullusi'nnim, l.SlR), p. i;^7. 



