Occasional Papers of the Museum of Zoology 39 



similar shell to this subspecies. However, the typical form is 

 considerably smaller and the color is more pronounced. 



I did not collect this form at Aroa. but a set in the A. X. 

 S. P. (no. 12965), labeled as from that locality (C. F. Starke, 

 1872). agrees quite closely with the shells from the Cerritos de 

 Yumarito. 



Potcria dunkcri (Pfr.) and approaching var. pcrczi (Hidalgo). 

 Figs. v-S. U. 



Four adults and 17 immature specimens; from the brook 

 flats of a small tributary of Rio Lobaterita, near Estacion Ta- 

 chira ( H. I. b, 35), and from the steep valley-sides of the 

 larger stream itself (H. I, c. 38). 



As will be seen from the table of measurements, these 

 small lots of specimens show a great deal of variation, both in 

 size and shape. All of the specimens are more elevated than 

 either typical dunkcri or pcrcci. One specimen (fig. v-U) is 

 much larger than the others, and, in this particular approaches 

 P. d. dunkeri. The growth lines of all are well-marked, but 

 regular and closely spaced. The peristome is thickend and often 

 narrowly reflected, especially on the palatal wall. The number of 

 whorls varies from 4^4 to 4^; the umbilicus is from 1/3 to 

 I '4 of the major diameter. The ground color varies from 

 light olive-green to brownish-olive. The light, peripheral band 

 is poorlv marked, but is bordered below by a broad l)and of 

 darker color, which tends to be accentuated at its upper and 

 lower borders, or even to break up into a numlier of rather 

 indefinite l)ands. In some specimens, an additional dark band 

 is present on the umbilical side, as is characteristic of P. d. 

 pcrczi. while the sutural region also may be darkened. 



Four specimens, labeled \'enezuela (A. X. S. P. 12971), 

 connect this series witb typical P. d. dunkcri. Their measure- 



