PHYSA. 359 
Fischer and Crosse 2 figure an example with two dark spiral bands. A specimen 
found at Capetillo by Mr. Champion shows several narrow whitish spiral bands near 
the base of the shell. Younger examples from Santiago Zamora® are remarkably 
slender: long. 18, diam. 9, apert. 14 millim. 
Concerning the identification of P. purpurostoma with P. impluviata, I have before 
me a specimen collected by Dr. O. Stoll at Duefias which agrees exactly with the 
description and measurements given by Canon ‘Tristram °. Salvin, however, has sent 
me some others, under the name P. purpurostoma, from the first collection made at 
the lake of Duefias, which are much smaller, narrower, and pale coloured; I regard 
these as a variety of P. (Stenophysa) spiculata. 
Var. bocourti. 
Aplecta, sp., Stoll, Guatemala, Reisen und Schilderungen, 1886, p. 33 °. 
Physa influviata (Morelet), Sowerby, in Reeve’s Conch. Icon. xix., Physa, t. 2. fig. 167; Clessin, 
in Martini & Chemnitz, Syst. Conch.-Cab. ed. 2, Limneiden, p. 330, t. 46. fig. 2 (copied 
from Sowerby) *. 
Aplecta aurantia, var. bocourti, Fisch. & Crosse, Miss. Scient. Mex., Mollusca, ii. p. 86, t. 30. 
figg. 1, la’. 
Physa fuliginosa (Morelet), Biolley, Moluscos terr. y fluv. de Costa Rica, p. 17°. 
Comparatively larger, with more prolonged spire than in the type, thus approaching P. nitens ; colour golden- 
brown or chestnut-brown, some specimens with paler streaks; inside the aperture dark brown, and the 
columellar margin somewhat purple at its upper end, as in typical P. impluviata. 
a. Long. 28, diam. 15; apert. long. 21, lat. 9 millim. 
b. ” 24, 9 11; 9 153, ” 7 ” 
& 5 25, 4 12; ” 17, ,, 7 ” 
a. Fischer and Crosse’s measurements; >. From Sowerby’s figure ; c. Costa Rican specimen from Uruca. 
Hab. Yucatan: Palizada (Bocourt °). 
N. GuateMaLa: Coban (Bocourt °). 
CentraL GuaTEMALA: Laguna of Naranjo and at San Antonio near the city of 
Guatemala (Stol/°). 
W. GuatemaLA: Duefias, in the marshes around the lake (Stol/). 
CentraL Costa Rica: La Uruca, near San José, in a pond (Biolley 1°). 
Somewhat variable in form and colour, but, so far as I can judge, inseparable from 
the typical form of P. impluviata by any certain character. Sowerby” figures a 
specimen with unusually long spire; his spelling “ ¢nfluviata” is most probably 
a misunderstanding, or a supposed correction of zmpluviata. This name, given by 
Morelet, is derived from the Latin word “ impluvium,” a reservoir of water or cistern 
in the atrium of an old Roman house, referring to “ pluvia,” rain, not to ‘ fluvius.” 
Var. leta,n. (Tab. XX. figg. 2, 3.) 
Physa aurantia (Carp.), Tristram, P. Z.S. 1863, p. 412 n 
Rather large and solid, somewhat more cylindrical than in the type, of a vivid golden-brown colour, with 
