212 S1MPULOPSIS. 



Genus SIMPULOPSIS Beck, 1837. 



Simpulopsis BECK, Index Moll., p. 100 MARTENS in Albers' 



Die Heliceen, p. 308 (type S. sulcidosa Fer.). PFR., Nomencl. Hel. 



Viv., 1878, p. 228 Simulopsis GRAY, P. Z. S., 1847, p. 171 (type 



" Helix sulcosa"). 



Shell imperforate, varying from globose to ovate, very thin, mainly 

 cuticular, usually with few whorls ; the last very large ; apical 1^ to 

 1^ whorls with excessively line spiral striation, except in subgenus 

 Platysuccinea ; apertuie large, rounded lunate or ovate, oblique; 

 peristome and columella very thin, simple and arcuate. Type S. 

 sulculosa Fer. 



The jaw is arched and composed of numerous plaits, as in Dry- 

 mceus ; radula about as in Bulimulus y but the cusps of the teeth are 

 more strongly developed. 



The species live on and among plants in moist woods. The group 

 was at first associated with Succinea ; Pfeiffer then placed the species 

 in Vitrina. It was recognized as agenus by Morch in 1852, and by 

 Shuttleworth in 1854; these authors being followed by Pfeiffer. Dr. 

 Paul Fischer, in 1873, was the first to recognize the Bulimulid affin- 

 ities of the group. 



The typical group of species occurs in Brazil, from the State of 

 Bahia to Sao Paulo ; but one species has been found in Trinidad 

 and another in Nicaragua. An aberrant group of forms with 

 smooth apical whorls is found in the West Indies and. Eastern 

 Mexico. Several old-world forms have been referred to Simpulopsis 

 (see p. 226), but their status is uncertain. 



Tlie species fall into three sections or subgenera : 

 I. Apical whorls spirally striate. 



1. Simpulopsis s. str. Short globose shells, excessively 

 thin, mainly cuticular, somewhat flexible, with 3 to 4^ 

 whorls ; corrugated or merely wrinkled, varying from 

 greenish-yellow to olive-brown. 



2. Bulimulopsis Pilsbry, 1899. Oblong-ovate or globose- 

 conic, higher than wide, smooth, glossy and brittle, Uyht 

 tinted ; whorls 4 to 5^. Brazil. (See p. 220.) 



II. Apical whorls smooth. 



3. Platysuccinea Ancey, 1881. Globose, thin, rather 

 brittle, with 2-| to 3^ whorls ; striated or smooth, light- 



