OF CONCHOLOGY. 



221 



been carefully examined, except in the Salinas valley, where no 

 Helices were found. On the east side of this valley the Mt. 

 Diablo range rises to 5,500 feet or more in height, and is very 

 arid, but as fossiliferous limestone occurs frequently, Helices 

 may be found in some localities. It was crossed only in one 

 place by Prof. Brewer, of the Geological Survey, near New 

 Idria, lat. 36° 30', and probably this was the locality of the 

 unique specimen described by me in the Proc. Cal. Acad., iii.' 

 260, 18fi6. I have since suspected this to be a hybrid between 

 H. ramentosa and Mormonum (p. 332), but I have no proof of 

 the latter occurring on this range, and now suspect that better 

 specimens will prove it to be a. distinct species, in which case 1 

 propose for it the name of H. Diabloensis. South of the above 

 point for 160 miles this range has not been explored by any 

 scientific collectors, and is probably the habitat of the H. Car- 

 penteri, Newc, said to be from " Tulare Valley," but not found 

 by collectors on the eastern side of that valley, which has been 

 frequently traversed. Mr. Gabb found a fossil specime'n some- 

 where in this latitude, referred to this species by Dr. Newcomb, 

 which looks wrinkled like exarata, but is nearly globular.* 

 Another so named by him, also broken and bleached, is in the 

 Cal. Academy's museum, but is much more depressed and 

 smoother, not unlike Traskii. The type having been lost on 

 the " Golden Gate," it will be hard to identify. It is not un- 

 likely that two or more distinct species exist in the range. To 

 the north of New Idria they are very scarce, ramentosa being 

 the most common and nearly peculiar, as will be mentioned 

 hereafter. 



Monterey is the most prominent point on the coast near lat. 

 36°30\ It is so exposed to the northwest winds as to be less 

 subject to dryness than any other part of the coast south of lat. 

 40°, and consequently the pines and cypresses of the mountains 

 southward here come down to the sea level. In the noble grove 

 at Cypress Point, and there only, is found the typical H. Dupe- 

 tithoudrsi, Desh., as isolated as if on an island. It may, how- 

 ever, be yet found on the mountain summits eastward among 

 similar vegetation, though probably modified. Those who con- 

 tend for the union of species differing only in sculpture, hirsute 

 surface or subangled form, would consider H. Traskii, sequoicola, 

 Mormonum and even Hillebrandi as forms of the same, but on 

 this more will be said hereafter. 



At Monterey is also the only habitat of the typical Califor- 



* I found H. Carpenteriana in the low foot hills of the Sierra Nevada, 

 a mile or two north of Pose creek. — W. M. Gabb. 



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