WEST COAST PULMONATA. 37o 



eastward contain many, but are so mucli drier that land pul- 

 monates are rare on tliem, and are the same species found 

 Avest of Livermore Valley. 



There is a dense growth of trees on many of the north and 

 east slopes of these hills, especially where springy, which 

 form shelter for such animals, but only one small grove of 

 pines grows two miles northeast of the peak on a very dr3r 

 sandstone ridge, and can have no effect on the land shells,, 

 being a species of the arid eastern slope of the range. 

 Toward the northwest, however, appears another of the 

 coast range species. No. 36, between 250 and 400 feet 

 elevation, along the belt of calcareous tufa before men- 

 tioned, wdnch runs about four miles N. W. through Pied- 

 mom Yalley, and the same distance S. E. 



It is accompanied by the largest number of species found 

 east of the bay. They are Nos. 1, 5, 9, 11, 12, 15, 17, 23, 

 28, 31, 36, while in scattered localities lower down are 

 found Nos. 6, 24, 25 42, 43, and near the bay shore Nos. 2 

 and 3 (introduced), 20 and 21 in gardens, 40, and Nos. 18,, 

 19 and 22 have been reported from the vicinity. Fires^ 

 clearing, and cultivation of the land, have no doubt mucli- 

 thinned out most of these, as few of them are found abun- 

 dantly. 



As none exist on the higher and steeper parts of the hills,, 

 the settlement of the lower more cultivable parts must tend 

 to cause a still greater scarcity of many of them, especially 

 those limited to this vicinity, Nos. 28 and 33. The tendency 

 of migration is chiefly downward, shells being carried hy 

 the winter freshets down the streams, but the more general 

 cultivation of the level lands tends to exterminate them, 

 Avith some exceptions hereafter noted. There formerly ex- 

 isted large colonies of some species in willow thickets and 

 meadows near the bay, but few are now found in such 

 places. I was told by an old resident that he once found 

 a large colony near Eedwood Peak, in a meadow near 

 a mill, and as I have not found any at the sawmills. 



