MADE BY DR. ANTONIO RAIMONDI IN PERU. 299 



Figures. Natural size. 



Locality. "A little distance from the town of Ollon." 



Remarks. This species is broader and more rounded on the sides than T. orni- 

 thocephala, Sowerby, the lateral margins of the valves are more sinuous, and it is 

 flatter towards the base, and the plications on the smaller valve are wanting in that 

 species. In the absence of plications on the dorsal valve, it differs from all the 

 other species described from South America. '^ 



RHYNCHONELLA, Fiscli. 



R. Antonii, n. s., PI. 42, fig. 10, 10a. 



Shell triangular, widest about a third of its length from the base,' which is 

 rounded; sides sloping nearly straight from the beak at an angle of about '70° 

 from each other; beak narroAV, elevated; area large. Large valve bearing a broad 

 shallow sinus, ending in a correspondingly broad, short tongue which encroaches 

 on the small valve. Smaller or ventral valve regularly convex on the surface 

 except close to the base, where the side of one rib is carried down to fit the side 

 of the tongue of the opposite valve. Surface ornamented by about eighteen radi- 

 ating ribs, of which usually six are in the groove of the dorsal valve and seven 

 corresponding with those on the ventral; in one example there are eight on the 

 dorsal and nine on the ventral valves in the middle. 



Figures. Slightly magnified. 



Localities. Three specimens marked " Cerro de San Antonio, with mines of 

 silver." This locality is also given for Pecten argentariiis, but the rock is different 

 lithologically. Another specimen is marked " Quebrada de Colpamayo, near 

 Chota," the locality of Placunanomia lima. This agrees lithologically with the 

 other specimens of the same species, but also differs from the other fossils of the 

 locality. Still another specimen in a coarse red sandstone is marked " Cerro de 

 Vivuco, a league and a half from Ollon." Thus two of the three lots are said to 

 come from Cretaceous localities or neighborhoods, but all three differ in the cha- 

 racter of the rock from the other fossils. We have, therefore, no reliable clue to 

 the geological age of the species. 



ECHINODERMATA. 



ECHINUS, Linn. 



E. BOLIVARTI, d'Orb., Amer. Merid., p. 88, PL 21, fig. 11-13. 



From the "Hacienda of Uchupata; Prov. of Huari. Cretaceous." 



