ORTMANN : TERTIARY INVERTEBRATES. 
273 
L & S Ostrea ingens. 
L Cucullcea alta. 
L Turrit ella ambulacrum. Geryon peruvianus. 
Turritella breantia7ia. 
The prevalence of Leonense species is opposed to the low level to 
which this locality belongs, especially when we come to compare it with 
the upper horizon at the same locality. All 5 species are found at Santa 
Cruz. 
Mount of Observation, upper horizon ; 25-150' above tides. 
J * Terebratella patagonica. 
*Nucula reticularis. 
S * Area patagonica. 
L& S* Ostrea ingens. 
Modiola ameghinoi. 
* Cardita elegantoides. 
P * Cardita incequalis. 
P * Cardium puelchum. 
* Venus meridionalis. 
*Mactra damvini. 
Mactra garretti. 
* Cor bid a hatcheri. 
* Mar tesia patagonica. 
S Dentalium octocostellatum. 
Calliostoma observationis . 
Turbonilla cuevensis. 
S * Sc alar ia rugidosa. 
* Infundibulum corrugatum. 
J Siphonalia noachina. 
S Voluta ameghinoi. 
* Cancellaria gracilis. 
* Cane ell aria cf. medince. 
Actceon semilcevis. 
Balanus varians. 
Of these 24 species, 15 are found at Santa Cruz (those marked*). This 
horizon would correspond to about the middle of the series at Santa Cruz; 
nevertheless it contains 2 distinctly Juliense, and no less than 5 Suprapat- 
agonian species, while Leonense species are hardly represented. 
On the other hand, 9 species are found here, which have not been 
found at Santa Cruz. These, however, cannot be taken as representing 
a “ Suprapatagonian ” fauna. 6 of them are either new species, or have 
not been found elsewhere ; of the rest 2 are found at San Julian (see be- 
low) at a much lower level ( Siphonalia noachina and Balanus varians ), 
and V. ameghinoi has been found at Lake Pueyrredon, 600' above base 
of Tertiary. That this latter locality cannot be regarded as Suprapata- 
gonian will be demonstrated below. 
According to stratigraphical evidence, we are to expect that this local- 
ity should belong to the upper Juliense or Leonense division of the Pata- 
gonian beds : instead of that, Suprapatagonian species prevail, while a few 
Juliense are intermingled with them. Thus it is impossible to say, to 
which of Ameghino’s and v. Ihering’s subdivisions the beds of this local- 
ity are referable. 
All the foregoing localities resemble more or less in the state of pres- 
ervation of the fossils and in the matrix the type-locality at Santa Cruz, 
and, indeed, geographically, they are not far distant from it. The first 
