364 



TERRESTRIAL AIR-BREATHING MOLLUSKS. 



Helix reticulata (Pfeiffer). 



Arionta ramentosa, Gould. 



Shell umbilicate, depressed-globose, solid, obliquely striated, and marked 

 Fi 245. with oblong, somewhat regular granulations 



formed by striae descending towards the an- 

 terior part ; yellowish with one revolving 

 reddish band ; spire shortly conic ; whorls 5h, 

 somewhat convex, the last broad, rounded, 

 not falling in front ; umbilicus narrow, not 

 pervious ; aperture diagonal, roundly lunate ; 

 peristome wbite, thickened, its ends not converging, the right scarcely ex- 

 panded, the columellar sloping, dilated above and reflected. Greater diam- 

 eter 22, lesser 18 mill. ; height, 11| mill. 



Helix ramentosa, Gould, Proc. Bost. Soc. Nat. Hist., VI. 11 (1845) ; Terr. Moll. 



U. S., III. 12. — Pfeiffer, Mon. Hel. Viv., IV. 349.— W. G. Binney, Terr. 



Moll., IV. 13. 

 Aglaja ramentosa, Tryon, Am. Journ. Conch., II. 314 (1862). 

 Helix Parkeri, Tryon, 1. c, III. 105. 

 Helix reticulata, Pfeiffer, Mai. Blatt., 1857, 87 ; Mon. Hel. Viv., IV. 270 ; 



Nov. Conch., I. 120, PI. XXXIV. Fig. 47. — W. G. Binney, Terr. Moll., IV. 



12 ; L. & Fr.-W. Sh. I. 169, Fig. 294 (1869). 

 Helix Bridgesii, Newcomb, Proc. Cal. Acad. Nat. Sci., II. Fi K- 246. 



91 (1861). 

 Aglaja Bridgesii, Tryon, Am. Journ. Concb., II. 313 



(1866). 



Napa County, to Santa Clara County, California, in the 

 California Region. 



Fig. 245 is a fac-simile of one of Pfeiffer's. 



Specimens of Helix Bridgesi received from Dr. New- 

 comb resemble forms of A. ramentosa so closely that I be- 

 lieve the two to be identical. An authentic specimen, 

 loaned by Dr. Newcomb, is figured here. The name 

 Parkeri was suggested, as Bridgesi was preoccupied in 

 the genus Helix. mix ^goi. 



The above description is of the form known as reticu- 

 lata. The original description of ramentosa here follows. There can be no 

 doubt of the identity of the two forms. 



Shell perforate, suborbicular, depressed, thin, reddish, with a smoky, white- 

 margined band revolving at the periphery ; granulated with incremental lines 

 and equally oblique, decussating furrows ; whorls 5^, rather convex, the last 

 obtusely angulated ; suture deeply impressed ; aperture obliquely oblong-ovate ; 

 peritreme acute behind, white, decidedly reflected towards the umbilicus ; throat 

 reddish. Greater diameter, 20 mill.; height, 12 mill. 



Jaw stout, strongly arcuate, dark horn-color, transversely striate ; ends but 



