148 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



Beds of San Rafael age occur in the vicinity of Tampico, 

 both to the west of the city and between the city and the Gulf. 



Among the best exposures of these deposits in the region 

 under discussion are those found in the Topila Hills, 15 miles 

 southwest of Tampico, where there are many good exposures 

 of beds of limestones with characteristic fossils. There are also 

 numerous exposures to the south, although where the limestones 

 and fossils are lacking the identity of the beds is not so easily 

 determined. 



Jeffreys, in describing his Temapache section, which seems 

 to belong to this stage, states that succeeding what he calls the 

 Mendez series, there is a dark bituminous sandstone containing 

 sharks' teeth and nummulites, overlain by limestones and occa- 

 sional conglomerate carrying ostrea, pectens, nummulites, and 

 turritella. Above this comes a hard, coarse to fine-grained 

 limestone, replaced upwards by a hard, coarse yellow limestone 

 with calcareous sandstone, as in the Ozuluama beds, carrying 

 turritella, ostrea, and pectens. The top of this section is the 

 hard Temapache limestone. Still another section is given in 

 the Cuchares River area which shows limestones and thin beds 

 of shale overlain by calcareous sandstone, and this by Le Pena 

 gray limestone with nummulites. Above this there are beds of 

 semi-crystalline limestone, some of them being highly fossil- 

 iferous, while the top is formed of turritella limestone inter- 

 bedded with yellow calcareous sandstones. 



The fossils found in the San Rafael stage include the fol- 

 lowing : 



Foraminifera i^" 



Orbitoides epphippium 



Nummulites radiata ? 

 Corals :-^ 



Orbicella cellulosa Duncan 



Orbicella, n. sp. 



Maeandrina, n. sp. 



Acropora, sp. ? 



Favites ? polygonallis Duncan 



Goniastrea antiguensis Duncan 



Goniopora, sp. very similar to, or identical with, an 

 Antiguian species. 



^* Determinations by R. M. Bagg. 



" Determinations by T. Wayland V^aughan. 



