SIMPULOPSIS. 217 



Helix (Succinea) rufovireits MORIC., Mem. Soc. Phys. et Hist. 

 Nat. Geneve, xi, p. 147, pi. 5, f. 4 (1845-6). Vitrina rufovirens 



PFR., Monogr. ii, p. 511 Simpidopsis rufovirens PFR., Conchyl. 



Cab., p. 30, pi. 3, f. 3, 4; Monogr. v, p. 22. Simpulopsis rufescens 

 MOR., ADAMS, Gen. Rec. Moll, ii, p. 128. 



This species from tlie number of specimens before me, must be 

 found in some abundance. It is wider than sulculosa, with fewer 

 whorls, lower spire and finer corrugation. The spire is decidedly 

 more raised than in brasiliensis, and the outer lip is inserted lower. 

 The deep, rather fine and even corrugation is its most prominent 

 feature. 



S. CORRUGATA Guppy. PI. 64, figs. 93, 94, 95. 



Shell globose, very thin and fragile, being mainly cuticular ; light 

 green, translucent in places. Surface glossy, deeply corrugated, the 

 ribs subregular, but in places a little irregular. Spire short., conic. 

 Whorls 3^, the earlier 1| smooth ; last whorl inflated, rounded. 

 Aperture large, subcircular, but somewhat excised by the penult, 

 whorl, moderately oblique; peristome thin, regular arcuate; colu- 

 mella arcuate, thin; no perceptible parietal callus. 



Alt. 9.3, diam. 9, longest axis of aperture 7.7, width 5.7 mill. 

 Trinidad, near Savana Grande, in humid forests ; rare (Guppy). 



S. corrugatus GUPPY, Ann. and Mag. N. H. (3), xvii, 1866, p. 

 53. S. corrugata Guppy, PFR., Monogr. vii, p. 28. GUPPY, 

 Journ. de Conchyl. 1878, p. 323, pi. 10, f. 3; Journ. of Conch, vii, 



1893, p. 221 BINNEY, Bull. Mus. Comp. Zool., v, p. 338, pi. 1, f. 



G (dentition). CROSSE, Journ. de Conchyl., 1890, p. 46 S. rufo- 

 virens Mor., E. A. SMITH, Journ. of Conch., viii, p. 244. 



Similar to S. rufovirens, but constantly smaller, of a lighter green 

 color when in good condition, and with the aperture perceptibly less 

 obliqii'-. 



Mr. E. A. Smith unites corrugata to rufovirens as a synonym, but 

 the differences indicated above are constant in the series before me, 

 and with the wide geographic separation of the two forms, seem to 

 make it desirable to retain the species or subspecies. u Species," 

 however, among the slightly differentiated forms of this genus, are 

 more conventional than usual; and in this instance we totally lack 

 material from the vast intermediate region, the Amazon valley. 



