THE NAUTILUS. 



Vou XXI. APRIL, 19O8. No. 12. 



NOTES ON PLATE XI. 



Several references to the figures grouped on this plate were pub- 

 lished before the plate was made up, and require correction in the 

 text. 



Figs. 1, 2, 3, Polygyra marteusiuna Pils., Tampico, Mexico. 

 Described in the July number, p. 26. The dimensions are wrongly 

 given in the text. The type measures, alt. 5.5, diain. 11 mm., 

 another specimen, alt. 4.8, diam. 8.8 mm. 



Fig. 4, Flumiiricola minntissima Pils. Idaho. Description in 

 November number, p. 76. Alt. 1.5 mm. 



Fig. 5, Vertigo occidentalis Sterki. Bluff Lak^. San Bernardino 

 Co., California. Described on p. 90. In our opinion this form 

 should be ranked as a subspecies under V. modesta nearest to V. 

 modesta castanea St., from which it differs in the shorter, wider, less 

 cylindric shape, and the slightly larger teeth. If this view is correct 

 it will stand, as V. modesta occidentalis, among several other slightly 

 differentiated races of modesta, all variable, and especially developed 

 in the Canadian zone of the Rocky Mountains. 1 V- m. occidentalis is 

 illustrated from the unique type, by courtesy of Mr. S. S. Berry. 

 It is No. 1860 of his collection. See also p. 123. 



Figs. 6-10, Micrarionta desertorum Pils. & Ferr. Described on p. 

 134. H. A. P. 



'See in this connection the figures in Pilsbrj and Vanatta, Partial Revision 

 of the American Pupae, 1900, p. 600, pi. 23. 



