392 PROCEEDINGS OF THE ACADEMY OF [May, 



(2) Var. scammoni (pi. XVI, figs. 34, 35, 36). Small, with many 

 or few narrow brown bands (translucent gray in fossil or dead shells), 

 continuous or nearly so, sometimes wanting. Columellar tooth 

 usually developed, often weak, sometimes wanting. 



Alt. 



Magdalena Bay (W. M. Gabb), 14 specimens. 



Pfeiffer's fig. 13 (copied in my text-fig. 2, d) was probably this 

 variety, which I name for Capt. Scammon, who has given a good 

 account of this coast. 



(3) Var. aspersa (pi. XVI, figs. 37, 38). Small, last whorl ^Zo6ose, 

 spire short. With wide marbled brown bands resembling those of 

 M. veatchii or Helix aspersa in pattern. Columellar tooth distinct or 

 indicated. 



Alt. 17.3, diam. 20 mm.; 4f whorls. 

 " 14.8, " 17 " 



Magdalena Bay (W. M. Gabb). 



(4) Var. exanimata Cooper, Proc. Col. Acad. Sci. (2) III, p. 216, 

 pi. XIV, fig. 7, from Espirito Santo Island, in the Gulf of California, 

 is known "to me only by the original account. I would expect it to 

 be specifically different. It is the only form of this group yet found 

 on the gulf side of the peninsula. 



Helix decorata Pfr. (Conchyl. Cab., p. 249, pi. XXXVI, figs. 14, 15), 

 the locality of which is unknown, may be a fully colored, thin, de- 

 pressed form of areolata. It has been referred to H. pisana with 

 doubt, and seems to-be a ''lost species. " It is not Helix decorata Fer. 

 I have copied the figures of decorata in text-fig. 3. 



^ «x«^ ^ 



Fig. Z.-^Helix decorata Pfr., copied from the Conchijlien Cabinet. 



Explanation of Plates XV, XVI. 



Plate XV. — Figs. 1, 2, 3. — Micrarionta veatchii 'Nc' Tryon. North end of 

 Cerros Island. H. N. Lowe. A. N. S. P. No. 106,016. 

 Fig. 4.—M. veatchii. Cerros I. Gabb. No. 10,261. 

 Fig. 5.—M. veatchii. Cerros I. Hemphill. No. 60,034. 



