262 PROCEEDINGS OF THE ACADEMY OF [Mch., 



under my scalpel, gives reason for considering its modification in this 

 species of importance. 



I have identified these shells with S. rowelli (Newc), a species said 

 to have been collected in Arizona by Frick, many j^ears ago. S. arizo- 

 nensis (Dall), from Tucson, is more elevated, but is probably related 

 to rowelli. 



A form collected by Dr. G. H. Horn, the coleopterist, at Fort Grant, 

 Arizona, is closely related to the shells described above. 



In the Patagonia Mountains, a short distance eastward from the 

 locality of S. rowelli, a smaller form of the species was collected by Mr. 

 Ferriss (PI. XVIII, fig. 35), and also by Mr. Ashmun. The umbilicus 

 is narrower and more covered by the dilated lip than in Sanford's 

 rowelli, and the last whorl descends more deeply in front. The shells 

 measure : 



One of Mr. Ferriss' specimens (fig. 35) was sent alive, and proves to 

 be like the Sanford's rowelli anatomically, differing merely in the 

 smaller size of all the organs, except that there is no perceptible flagel- 

 lum (PI. XX, fig. 20, the terminal ducts only are drawn). The jaw 

 (PI. XXIII, fig. IS) has about 6 narrow^ equal ribs. 



The type measurements of H. rowelli given by Newcomb are alt. .4, 

 diam. maj. .6, min. .5 inch., about ecjual to 10, 15, 12.5 mm. The type 

 is in the collection of Cornell University. 



Sonorella granulatissima Pils. PL XVII, figs. 21-23. 



Nautilus, XVI, p. 32, 1902. 



Bartsch, Smiths. Misc. Coll., Vol. 47, p. 193, PI. 32, fig. 4. 



The shell in the co-types of this species is thin, pale, with a rather wide 

 dark chestnut band without white borders, and visible above the suture 

 on the last 2h or 3 wliorls. The surface is very minutely and very 

 densely granulated over the usual low growth-wrinkles. Near the 

 periphery some faint traces of spiral lines may be deciphered in places, 

 but they are so slight that they would have been overlooked if not espe- 

 cially looked for. The umbilicus is small. The two co-types measure f 



* These measurements differ slightly from those given in the original descrip- 

 tion, due to the fact that at that time I used only a flat millimeter rule, upon 

 which it is, I find, impossible to read correctly the dimensions of globose shells. 



