416 MOLLUSCA. 
Nearer A. dysoni, Hanley, than A. malleata, Fisch. & Crosse. I have seen one of 
Strebel’s specimens. 
Var. prasina. 
Ampullaria malleata, var. n. prasina, Fisch. & Crosse, loc. cit. p. 235, t. 48. figg. 4, 4a°. 
Shining dark green, with distinct bands, peristome yellowish. 
Hab. E. Mexico: Misantla (Fischer & Crosse *). 
Strebel (Joc. cit. p. 26) gives the diameter of the aperture in his largest specimen (a) 
as 20 millim., but in his figure 13, taken from the same shell, it measures 23 millim. 
Fischer and Crosse® give for A. prasina, apert. long. 36, diam. 26 millim.; but on 
measuring their figure 4, I find the dimensions to be 34 and 24 respectively, although 
the length of the whole shell is 51 millim. in the figure and 50 in the description. I 
have corrected these measurements in the comparative table of the species (anted, 
p. 407), because the original statements of the authors would imply a greater difference 
in form between A. strebeli and A. prasina than is proved by their figures. 
4, Ampullaria innexa. 
Ampullaria innexa, Crosse & Fisch. Journ. de Conch. xxxviii. p. 111 (1890) *; Miss. Scient. Mex.,. 
Mollusca, ii. p. 242, t. 44. figg. 7, 7 a-c’. 
Globose, but with rather produced conical spire; outer margin of the aperture much arcuated, thin, pale 
coloured. 
fab. 8. CzentraL Mexico: Monte de Mistam near Coapam, State of Oaxaca ?. 
S.W. Mexico: on the Pacific shore, in the same State } 2. 
This form is rather near A. strebelz. 
5. Ampullaria eumicra. 
Ampullaria eumicra, Crosse & Fisch. Journ. de Conch. xxxviii. p. 118 (1890)*; Miss. Scient. Mex., 
Mollusca, ii. p. 243, t. 48. fig. 10°. 
A small thin shell, resembling A. flagellata. 
Hab. 8.W. Mexico: State of Oaxaca (Ghiesbreght ?). 
Perhaps a young state or dwarf form of A. violacea, Val. 
6. Ampullaria monachus. 
Ampullaria monachus, Crosse & Fisch. Journ. de Conch. xxxviii. p. 112 (1890)'; Miss. Scient. 
Mex., Mollusca, ii. p. 250, t. 46. figg. 5, 5a’. 
A somewhat broad, ovate form, with short spire, dark greenish-brown, with thin pale yellowish peristome. 
Hab. S. Mexico: Santa Efigenia, on the Isthmus of Tehuantepec (Sumichrast 2). 
Resembles broad forms of A. flagellata. 
