NEW SNAILS—PARODIZ 431 
In comparison with this new species, I have reviewed eight speci- 
mens of the original type lot of Bulimulus gorritiensis Pilsbry 1897 
(USNM 157653) from Gorriti Island (the species also occurs on Lobos 
Island), which proved to be a very different form (fig. 14): B. corderot 
is larger, more elongate and thinner, with less convex whorls, a nar- 
rower base of the aperture, a shorter spire with more horizontal 
suture, a paler color, and the columellar lip not twisted to the 
left; it is also more easily distinguishable from B. bonariensis monte- 
vidensis Pfeiffer, 1846 (=sporadicus montevidensis). 
This species is dedicated to the late Dr. Ergasto H. Cordero, former 
Director of the Museo de Historia Natural de Montevideo, and a 
great contributor to our knowledge of the invertebrate fauna of the 
countries of the Rio de la Plata. 
Bulimulus mecei, new species 
PLATE 2, Figure 13 
Shell rimate perforate, very globose, thin, calcareous, white. 
Whorls 6%, the last occupying four-fifths of the total length. Spire 
very short with suture sinuous, marked with the initiations of folds of 
growth which are very irregular and especially conspicuous on the last 
half of the body whorl; no other type of sculpture present. The worn 
protoconch shows traces of vertical waved lines. Aperture nearly 
two-thirds the total length and equal to the lesser diameter. Columel- 
lar lip triangular, very broad above, covering in part the perforation; 
peristome very thin. 
Holotype (USNM 349118) from the northeastern part of the prov- 
ince of Salta, Argentina, at 800 feet, collected by D. S. Bullock, July 
28, 1921. Measurements: Height 25 mm., larger diameter 19.5 mm., 
lesser diameter 17 mm., last whorl 21 mm., aperture 17x10 mm. 
There is another smaller specimen, (USNM 109594) collected in Peru 
by S. J. Emmons of the U.S. Geological Survey, which is assigned 
provisionally to this form, but it differs in being variegated like B. 
apodemetes d’Orbigny, 1835, and in having no traces of nepionic 
sculpture pl. 2, fig. 12). 
The largest diameter is not, as in other Bulimuli, between the 
anteroposterior margins, but is across the dorsal-ventral line; for this 
reason it seems to be one of the most obese forms of Bulimulus. 
Compared with moei, apodemetes d’Orbigny is smaller, slenderer, and 
has more corneous stripes and spots. Compared with B. apodemetes 
dispar Hylton Scott, 1952, from the same province of Salta, our new 
species is larger, has a more rounded aperture, and the last whorl is 
more dilated; dispar is also less obese than apodemetes, a remarkable 
difference. 
