212 
Psyche 
[June 
Fig. 2. Agonum ( Platynella ) districtum (Casey). Zempoala, Morelos. 
A. Head and pronotum. B. Apices of elytra. 
Fig. 3. Agonum ( Platynella ) tolucense (Straneo), head and pronotum. 
Nevado de Toluca, Mexico. 
conspicuous sclerites; parameres conchoid, the right smaller. Type 
species of subgenus: Anchomenus (Platynella) districtus Casey 
(1920, p. 24), here designated. 
Discussion : Platynella appears to be limited to the central high- 
lands of Mexico, along the Sierra Volcanica Transversal from Mich- 
oacan to Veracruz. I have not studied Casey’s four species with 
