ORTMANN ! TERTIARY INVERTEBRATES. 
309 
Mr. Hatcher’s observations indicate the existence of such beds near San 
Julian. He discovered marine beds unconformably overlying the Pata- 
gonian beds at Darwin Station (Hatcher, 1900 a, p. 108). Here he col- 
lected only two species : Ostrea patagonica and Trophon laciniatus var. 
inornatus. The latter form most distinctly points to the Cape Fair- 
weather beds, but the oyster is different. It is this the southernmost 
locality at which the true O. patagonica has been found, and the associa- 
tion of this Entrerios oyster with the Cape Fairweather Trophon suggests 
very strongly that both deposits may be identical in age, and that their 
difference may be due to their geographical location : then the Miocene 
Patagonian Ostrea ingens would remain the identical species in Pliocene 
times in the south, while it changes into O. patagonica in the Pliocene 
farther north. 
It is not impossible that our locality at Darwin Station is identical with 
one of the type localities of Ameghino for the marine Tehuelche beds. 
V. Ihering (1897) mentions four species (O. ferrarisi = patagonica, Pecten 
actinodes , Scalaria rugulosa var. obsoleta , and Trophon varians = laciniahis 
var. inornatus') from a locality between Santa Cruz and San Julian, which 
he spells: Santa Rosa (pp. 225, 277, 296), Punta Rosa (p. 227) and Pta. 
or P. Rasa (pp. 322 and 323). Since the latter form is given for the 
same species, for which Santa or Punta Rosa is quoted, there is no doubt 
that the same place is intended. Mr. Hatcher informs me that he has the 
vague impression that the peninsula between the bay of San Julian and 
the sea is called “ Punta Raza ” by the sailors. If that is true, it is very 
probable that our locality at Darwin Station is not very far from, if not 
identical with Ameghino’s Punta Rasa, since it is situated near the base 
of this peninsula. Punta Rasa is said to represent “Tehuelche” beds, 
and of the four species mentioned by v. Ihering, we possess 2 from Dar- 
win Station ( Ostrea patagonica and Trophon inornatus ), and 2 from Cape 
Fairweather (. Pecten actinodes and Trophon inornatus). This fact also is 
much in favor of the view that Hatcher’s locality at Darwin Station as 
well as the Cape Fairweather beds belongs to the same horizon as v. 
Ihering’ s and Ameghino’s Punta Rasa. 
Another locality, which corresponds stratigraphically with the Cape 
Fairweather beds, has been discovered by Mr. Hatcher at Fake Pueyr- 
redon, where marine beds again overly the Santacruzian beds, and cap 
the whole “Rio Tarde section” (Hatcher, 1900 a, p. 108). Only two 
