70 ODONTOSTOMUS. 



examples of form (i), in 1 of 2 specimens of form (r), but in none of 

 the 9 mature shells of form (rf). A suprapalatal fold thus occurs 

 only in the relatively stout forms, and here only in the minority of 

 the specimens. Similarly tlieie is a weak, narrow fold inward from 

 and near the upper palatal fold, in 2 of the 9 specimens of form (rf), 

 but in no others. The same fold occurs in one of four specimens 

 similar to form (e), collected at Corumba by Rhode, and in another 

 shell from unknown locality [also in several examined by II. A. P.]. 

 The lower palatal fold is present in all the specimens taken by Dr 

 Bohls. 



Typical SPIXI Orb. PI. 12, figs. 60 (type), 01, 02, G3. 



This is the comparatively small and slender form, with four teeth, 

 described above. In my opinion the supposed species striatus Spix 

 and Wagner (fig. CO), spixii Orb., turrita Anton, conspersa P. & M., 

 and wagneri Pfr. (figs. 62, 63), are completely identical. The 

 Paraguay form defined by von Martens as var. " (c) spixi Orb., 

 shorter [than bohlsi~\ but rather stout, 33 mill, long, 10^ wide, with 

 10-10^ whorls " belongs here " as well as specimens collected by 

 Rhode at Corumba in Matto Grosso." Also var. " (rf) wagneri Pfr.; 

 short and narrow, 2631 mm. long, and only 9 wide, 10^-11^ 

 whorls." One specimen of var. (e) has a suprapalatal fold, like the 

 much more slender var. minor Orb. 



Var. UOIILSI v. Mart. 



" The longest specimens, 48-50 mill, long and only 12 or 13 

 wide, the measurement taken to include the outer lip, as usual, thus 

 very slender; the aperture 12 mill, long, and including the columellar 

 margin, 9 wide. Whorls 13-14, with weak vertical stria 1 . Color 

 whitish-gray, with broader or narrower zigzag streaks of rather 

 light brown." All the specimens have 4 teeth. Barranca de la 

 Novia, Paraguay. 



Var. MAJOR Orbigny. PI. 12, fig. 66. 



D'Orbigny, whose great name is due not less to his mastery of 

 detail than to the vast extent of his works, writes that he found two 

 quite distinct local varieties of spixi. One which he calls var. 

 major is always large, almost smooth, or at most marked with quite 

 distinct string and invariably has only four teeth ; it is moreover 



