DESCRIPTION OF THE PLATES. 19^ 



PLATE II. 



Fig. 1. — Section of the beds marked e, figure 4, plate I. These are the most recent beds in the 

 valley Santa Margarita. 



a, a, a, the valley level with alluvium. 



A, B, C, the three hills containing the fossiliferous beds, dipping S.W. ; at b the agatic or 

 flinty layers occur 16 inches thick. 



1, 1, 1, calcareous layers of comminuted shell and large shells of Osirea titan; this is the first 

 bed of chapter 5. 



The second bed, B, has at 2 a broken shell bed, with specimens of Ostrea and Hinnites. The 

 third bed is represented at C, where 3 shows the Ostrea and Hinnites bed, and 4 the Ostrea 

 and Astrodapsis, with Pecten discus. 



At C 5, the upper layer of sandstone, pierced by pholadines, is situated. 

 Fig. 2. Section of the Santa Lucia mountains. This section was taken where the Santa Maria 

 river caiions through to reach Guadalupe Largo. The rock apparent in the axis is 

 serpentine, s, s, which is here made to repose on granitoid rock, although no granite was 

 actuallj' observed. The serpentine is cut through by dykes of augitic rock. Conform- 

 able to the serpentine on each side is, 1, thick beds of conglomerate, similar to that 

 underlying Santa Margarita valley. 2 and 3 are tlie brown and yellow sandstones of the 

 same age wi:h the Gavilan and Salinas valley bads. 

 Fig. 3. — Section of Greater Panza hill ; the lesser hill is similarly constituted. Th^y lie with 

 their greatest length N.W. and S.E. ; the upheaving rock, g, quartzose granite, lying at 

 the southern end ; e, brown sandstones similar to those of Santa Barbara ; /, an interval, 

 not observed, probably the heavy conglomerate ; b, c, d, coarse and fine grits and sand- 

 stones with views of gypsum and limonite. 



a 1 represents the beds containing Ostrea, Pallium and Astrodapsis, &c. 



a 2 is the soft argillite, with casts of Area. 

 Fig. 4. — Outline of Santa Maria valley, with its terraces, from near ranche Cuatro Domingo. 



A, the western slope of the San Jose mountains ; C, the slopes of the Santa Lucia ; B, the 

 intervening insular mass of strata, a part of the San Jos6 range, from which it is 

 separated by denudation ; D, present valley of the Santa Maria ; E, ancient water bed ; 

 D 1, present river bottom and first terrace ; 2 and 3, terraces above, the upper one corre- 

 sponding to the summit of the central islet and somewhat below the terrace level on the 

 Santa Lucia, 4. 

 Fig. 5. — Section of the San Jose mountain range, taken from valley San Jose across to Panza 

 ranch and valley ; still more to the east lies Panza hill. The axis of this range is the 

 felspathic granite with epidote, g ; uplifting the conglomerate, /, on each side, this bed 

 forms the summits of the hill range ; e, green gritty sandstones, fine texture ; d, coarse 

 conglomerate of porphyry and jasper of a reddish tint ; c, brown and yellow sandstones, 

 similar to those of Gavilan and Salinas valley ; b, a bed of green conglomerate made of 

 serpentine and quartz pebble ; a, whitish sandstones and layers of arg llite,with gypsum 

 remains of Ostrea and Pallium. 



