BULINUS. 



9T 



- BULINUS, Adansox. 



Tentacles filiform, setaceous. Mantle simple-edged, and not 

 reflexed over the shell. Foot long, acuminate behind. 



Shell sinistrorsal, elongated, polished, thin ; spire 

 acuminated ; aperture naiTow, produced anteriorly ; 

 inner lip simple ; outer lip acute. 



Jaw (of B. hypnorum) strongly arched, narrow, 

 cai'tilaginous, brown. 



Bidinus differs from Physa in having a simple, unfringed. 

 mantle. The shell is also more slender and more highly polished. 

 It is less common in North America than Physa, but usually 

 appears of a large size. Bidinus jyrincejjs, Phillips, of Central 

 America, and some of the South American species, are remark- 

 ably well developed. 



Adanson's name Bidinus has priority over Aplexa, Fleming, 

 and Nauta, Leach, and is accompanied by a careful description 

 and excellent figure. 



Buliniis aurantiiis, Cakpenter. — Shell thin, ovate, smooth or 

 marked with very delicate incremeutal strise, orange Lorn colored, brown- 

 ish on the spire ; spire short, always eroded when 

 adult ; about seven swollen whirls ; aperture some- -pis. 166. 



what dilated ; lip very thin, arcuate ; columella 

 scarcely folded. • 



This fine species, which is generally named Physa 

 peruviana in collections, is quite distinct from the 

 types in the British Museum. It much more nearly 

 approaches Aplexa maugerse, which is believed to be 

 a Caribbsean species (not Californian, as stated by 

 Woodward, Man. II, 171). It differs in shape, which 

 is never so elongated, and in color, which is almost 

 always orange-horn, with a tendency to darker shades 

 in rays, below the suture. Shell swollen, thin, glossy, 

 with an extremely thin columellar lip projecting BuHnus aurantius. 

 beyond the aperture, and indented at the base of the 

 body whirl. The length of the spire varies in different specimens, as does 



' I have been unable to obtain living specimens of a native species to 

 figure. Fig. 165 is from Moquin-Tandon. 



