ORTMANN : TERTIARY INVERTEBRATES. 275 



proaches more that of the mouth of the Santa Cruz River, is expressed in 

 the higher percentage of species that are also found at Santa Cruz, 

 although this difference from Oven Point is very slight. 



Both San Julian localities have 9 species in common, but the abundance 

 of the respective species at each locality is very different. Taking to- 

 gether these two localities, we may regard them as the type of the Juli- 

 ense beds, since 7 of the 9 species mentioned by Ameghino have been 

 found here. But the fact, that i Leonense (Ostrea ingens], and 4 Supra- 

 patagonian species (Ostrea ingens, Pecten geminatus, Sea/aria ritgulosa, 

 Stntfhiolaria anieghinoi] have been found here, strongly points to the 

 conclusion, that these beds also represent what Ameghino calls "Supra- 

 patagonian." 



Two more localities on the coast are: Port of Deseado (Port Desire), 

 which has yielded only Pecten cf. centralis, and Port Madryn (New Bay, 

 Terr. Chubut), which has yielded Ostrea ingens from two horizons : be- 

 tween tides, and 25' above high tide. 



The following localities are situated more or less inland : they all have 

 a sandy facies, and often the matrix is composed of fragments of shells. 



Shore of Salt Lake, 10 miles north of the mouth of Rio Chico ; near 

 the base of the series, within 50' above barren Cretaceous sandstones. 



J Scutella patagonensis. J * Terebratella patagonica. L & S * Ostrea ingens. 



Even among this small number of species, a Leonense and Suprapata- 

 gonian is associated with two Juliense. 



Upper Rio Chalia ; beds immediately underlying the Santacruzian 

 beds, containing mammals. Top of marine series. 



J Scutella patagonensis. * Venus navidadis ( ? ). L * Turritclla ambulacrum. 



Melicerita triforis. S *Dosinia meridionalis ( ? ). * Valuta gradlior. 



J * Terebratella patagonica. * Panopea quemadensis. * Valuta dorbignyana. 



* Glycimeris ibari. Fissurella eurytreta. Verruca lavigata. 



L&S* Ostrea ingens. * Gibbula dalli. Balanus vatians. 



*Mytilus cf. chorus. S *Scalaria rugulosa. 



S *Lucina promaucana. * Ctcpidula gregaria. 



These beds which are undoubtedly near the extreme top of the marine 

 series, and which ought to be, according to stratigraphical evidence, Supra- 

 patagonian, contain among 19 no less than 14 species, which have 

 been found also at Santa Cruz (marked*). 4 of the species are charac- 



