﻿1 88 SMITHSONIAN MISCELLANEOUS COLLECTIONS [VOL. 47 



II. — Group of S. hachitana 



(Plate XXIX) 



This group is characterized by having - the neanic portion marked 

 by wrinkled growth-lines, over which pass many slender, more or less 

 continuous, irregular, wavy threads which extend from the summit 

 of the whorls obliquely downward and forward to the suture ; in 

 addition to these a second set of raised lines, somewhat less strong 

 and distinct, and equally irregular, pass in an opposite direction, i. e., 

 obliquely downward and backward from the summit to the suture. 

 These two sets of lines frequently meet, forming acute angles at 

 their junction. The general effect might be termed subareolate. 



III. — Group of S. magdalenensis 

 In this group the neanic portion is found to be marked by one set 

 of fine, distinct, raised lines which extend from the summit of 

 the whorls in a very oblique curve downward and backward to the 

 periphery ; while another set of the same character extends in a very 

 oblique curve upward and backward to the periphery, where they 

 meet the first set, forming acute angles. These raised lines are quite 

 regularlv spaced, and the spaces between them appear minutely 



pitted. 



IV. — Group of S. Usheri 



(Plate XXX) 



In this group the transverse wrinkles or lines of growth are 

 stronger than in the preceding groups. No raised lines are present ; 

 only here and there do we find traces of a few distant, irregularly 

 scattered, low. oval, raised papilla?, the long axis of which is at right 

 angles to the lines of growth. 



Group of 5\ wolcottiana 



SONORELLA WOLCOTTIANA Bartsch 



(Plate XXXI, figure 4) 



Sonorella walcottiana Bartsch, Proc. Biol. Soc. Washington, vol. xvi, 



pp. [03-104, C903. ( Typographical error.) 



Sonorella wolcottiana Bartsch, Proc. Biol. Soc. Washington, vol. xvn, 



p. 101, 1904. 



S. zvolcottiana B. is the largest member of this group. The type 



(No. 170,007, l'. S. Nat. Museum) measures: maj. lat. 23.5 mm., 



min. lat. 18.5 mm., alt. 15.5 mm.; aperture: maj. lat. 14 mm., alt. 12.7 



mm. The fact that the broadly expanded and decidedly reflected 



columella almost conceals the umbilicus will readily differentiate it 



