22 
MOLLUSCA. 
1. Cenrrat Mexico, N. of the tropic. 
Helicina durangoana and H. borealis. 
2. CenTRAL Mexico, between the tropic and the Isthmus of Tehuantepec. 
Helicina ghiesbreghti and H. tenuis. 
3, WESTERN SLOPE OF Mexico, between the same limits. 
Helicina punctisulcata, H. fragilis. 
4, EASTERN SLOPE oF Mexico, between the same limits, chiefly State of Vera 
Cruz. | 
Helicina cinctella, H. zephyrina (turbinata), H. deppeana, H. cordillere, H. chryso- 
cheila, H. tenuis, H. fragilis, H. succincta, H. delicatula, H. owentana, var., 
H. notata, H. flavida, H. lirata, H. mohriana. 
Schasichetla nicoleti, S. pannucea, S. alata. 
Proserpina eolina, P. salleana, P. berendte. 
This large number is due chiefly to the circumstance that many collectors, and among 
them some very zealous and exact, have collected in this district for a considerable 
time. 
5. SOUTH-EASTERN Mexico, Chiapas, Tabasco. . 
Helicina ghiesbreghti, H. tenuis, H. oweniana, H. flotida, H. lirata. 
6. YUCATAN. 
Helicina tenuis, H. arenicola. 
7. British HonpvurRAs. 
Helicina dysoni. 
8. NorrH-west GUATEMALA, Valley of the R. Usumacinta below Salinas. 
Helicina amena, H. tenuis, H. fragilis, H. oweniana, var., H. flavida. 
Schasicheila pannucea. 
9. Nortu-east GuaTEMALA, Valley of the R. Polochic and of the R. Usumacinta 
above Salinas. 
Helicina amena, 1? ZH. sowerbyana, H. rostrata, H. tenuis, H. Fragilis, H. oweniana, 
var., H. flavida, H. chryseis, H. microdina. 
Schasicheila pannucea. 
10. Sours GuateMata, Pacific slope. 
Helicina ghiesbreghti, H. tenuis, H. lirata. 
Schasicheila pannucea. 
