164 BULIMULUS-BOSTRYX-LISSOACME. 



B. JUANA Cousin. PI. 1, fig. 9. 



Shell umbilicated, ovoid, and conic above; quite thick and dull ; 

 ashy-white, with three small tawny-brown bands, one at the suture, 

 the others submedian ; surface ornamented with irregular growth- 

 stride which are quite spaced and projecting. Whorls 7 2, slowly and 

 regularly increasing, separated by an impressed suture ; two earlier 

 whorls smooth, and with the following two corneous-brown ; follow- 

 ing whorls of spire with two brown bands. Last whorl plainly car- 

 inated around the quite large and deep umbilicus. 



Aperture oval, interrupted by the preceding whorl ; peristome 

 thin, sharp, the upper insertion a little above the lower band ; col- 

 umellar margin straight, with the traces of a canal at its union with 

 outer lip. Alt. 20-23, diam. 10-11 ; alt. of aperture 10, width 7 

 mill. 



Gualacco, province of Cuenca, Ecuador (Cousin). 



Thaumastus juan a COUSIN, Bull. Soc. Zool. France, xii, p. 228, pi. 

 4, f. 10 (April 1, 1887). 



Description abridged from Cousin. 



B. LAURENTII Sowerby. PI. 50, figs. 47, 48, 49, 50. 



Shell umbilicated, ovate-pyramidal, thin ; whitish with (1) numer- 

 ous (about 6) spiral brown bands (continuous or broken into a tessel- 

 lation), or (2) brown with darker streaks and a few median and 

 basal white spirals, or (3) unicolored white. Surface hardly shin- 

 ing, smooth except for faint growth-wrinkles. Whorls 6, convex, 

 the apex smooth. 



Aperture ovate, less than half the length of shell, showing the 

 external coloring within. Outer lip thin ; columellar lip dilated 

 above. 



Alt. 15j, diam. 9; alt. of aperture 6V mill. 



Alt. 14i, diam. 8; alt. of aperture 6 mill. 



Island of San Lorenzo, Bay of Callao, Peru (Curning and others) ; 

 Cero de las conchitas, near Lima (Paz). 



Bulinus ftmreniu SOWB., P. Z. S., 1833, p. 37. Bulimus laurentii 

 PFR., Monogr., ii, p. 213 ; Conchyl. Cab., p. 231, pi. 62, f. 28-30.- 

 DESH. in Fer., Hist., p. 86, pi. 157, f. 26-28. REEVE, Conch. Icon., 

 f. 119. HIDALGO, Journ. de Conch., 1870, p. 60. B, lorenzii ORB., 

 Voy, p. 281. POT. & MICH., Galerie, i, p. 146, pi. 13, f. 13, 14. 



With the form of B. modestus, this species lacks the coarse stria- 

 tion and is constantly much smaller. The color-patterns are numer- 

 ous. 



