80 OLIVA. 



Var. TREMULiNA, Lam. Figs. 46-52. 



This shows the same range of variation in color as the typical 

 irisans, and only differs in its greater size and solidity. 



Length, 3*5-4 inches. 



The synonyms are 0. nobilis, Reeve (fig. 48), 0. tenebrosa, 

 Marr. (fig. 49), 0. fumosa, Marr. (fig. 50), and 0. olynipiadina, 

 Duclos = 0. 2nca, Lam. (figs. 51, 52). 



Yar. ERYTHROSTOMA, Lam. PI. 1, fig. 3 ; PI. 26, figs. 53, 54 ; PI. 

 2*7, figs. 55-58; PI. 34, fig. 53. 



Shell cream- or flesh-color, with violet or red zigzag longitu- 

 dinal lines, which are very irregular and rather distant, and 

 frequentl^'^ shaded with orange ; there are two bluish violet 

 interrupted bands ; interior of aperture bright orange-red. 



Length, 2-3 inches. 



Ordinarily the coloring of this form is sufficiently distinctive, 

 so that I hesitated whether to give it specific or varietal rank ; 

 I am induced to favor the latter because a number of specimens 

 are before me which are intermediate between this and the last 

 variety : thus, some have the external coloration of eri/throstovia, 

 more or less, with the aperture white within, oth'ers are colored 

 like tremulina (some of them uniform dark chocolate^, with the 

 aperture varying from the faintest blush to deep orange-red. 



The synonyms are 0. magnifica, Ducros = 0. tremulina (in 

 part), Marrat (fig. 54), 0. azeinida, Duclos (fig. 55), 0. mazaris, 

 Duclos (fig. 56), 0. Sylvia, Duclos (figs. 57, 58), and 0. ponderosa, 

 Duclos (PI. 34, fig. 53), a thick-growing form. 



Var. TEXTiLTNA, Lam. PI. 27, figs. 59, 60. 



Cream-colored, very light yellowish or pink, closely reticulated 

 by zigzag chestnut markings, usually forming a superior and a 

 median band of darker reticulations ; aperture white or light 

 flesh-color. Length. 2-3 inches. 



This is also tjqjically a very distinct shell, in its close 

 reticulated pattern and in the bands being formed of darker 

 reticulations and not of markings confluent into blotches ; yet 

 in some specimens these blotches appear, and in others they 

 spread more and more so as to form a complete series from the 

 type to the uniformly chocolate-colored shell ; on the other hand. 



