H. A. Pilshry — Air-breathing 3Iolhisks of the Bermudas. 505 



Family SIPHONARIID^. 



Siphonaria brunnea Hanley. 



P. Z. S., 1858, p. 24. S. picta Sow. and S. alternata Say, of Heilprin's list. 



Differs from S. alternata in the more unequal ribs, but is perhaps 

 only a variety of that species. Cf. also iS. j^^cta D'Orbigny. This 

 form is. of course exclusively marine, and introduced here merely to 

 complete the list of air-breathing mollusks. 



Abundant on rocks between tides. — (A. E. V.) 



An undescribed species of Siphonaria was also taken. See a 

 subsequent article by Verrill and Bush in this volume (p. 524). 



Family TBUNCATELLIDiE. 



The species known from Bermuda may be determined by the fol- 

 lowing key : 



a. No noticeable crest behind the outer lip. 



b. Ribs close and numerous, regularly developed ; alt. usually 



6-7°^"^. T. caribmemis. 



b\ Ribs partially or wholly effaced on the convexity of each 

 whorl ; size usually smaller. T. caribceensis pulchella. 



a\ A strong, continuous crest behind the basal and outer lips ; alt. 



b. Ribs fine and close, 25-30 on the last whorl. T. bilabiata, 

 h\ Ribs strong and coarse, 13-15 on the last whorl. 



T. clathrus. 

 Truncatella caribeeensis ' Sowb.' ; Reeve. 



Plate LXIl, Figures 14, 14a. 



Typical specimens are in the collections made by Verrill and by 

 Heilprin. 



Truncatella caribeeensis pulchella Pfr. 



The specimens before me were collected by Robert Swift and C. 

 B. Adams, but they evidently found it in large numbers. Recorded 

 by Jones, 1876. 



Truncatella bilabiata Pfr. 



Plate LXII, Figure 12. 



Taken by Prof. Heilprin's class, and by Prof. Verrill's party. It is 

 the strong-crested Floriclian variety of the species, not the typical 

 form, which occurs in Bermuda, 



