1857.] BOLLAERT MASTODON REMAINS. 291 



described by Sir P. Egerton*. It is a whitish-grey micaceous sand- 

 stone containing crustacean fragments and coprolites, as well as 

 fishes, with several of the fossils before mentioned. 



Seeing that the Plectrodus mirabilis ?, Onchus Murchisoni ?, and 

 Lingula cornea, that characterize the lowest of these bone-beds, are 

 still present in this higher stratum, I might naturally class this mi- 

 caceous grey sandstone, though it be associated with some red and 

 green marls, as the last link of the Silurian series of life. But the 

 Cephalaspis Murchisoni, Egerton f, may be rather considered to in- 

 dicate that this stratum marks a true passage upwards into the Old 

 Red or Devonian System, while it constitutes the uppermost layer of 

 the so-called '* Tilestones." 



The copious development of red marls, thick-bedded sandstones, 

 and cornstones which follow, with the Cephalaspis Lyellii, Pteraspis 

 Lloydiiy &c., form the great overlying masses of Old Red Sandstone. 

 In conclusion, I would remark, that the Tilestones of Shropshire and 

 Herefordshire, which connect the Silurian and Devonian rocks, may, 

 according to the predominance of certain fossils, be classed either 

 with the inferior or the superior system. Their maximum thick- 

 ness mav be considered to be about 40 or 50 feet. 



3. On the Occurrence o/ Bones o/* Mastodon in Chile. By W. 

 BoLLAERT, Esq., F.R.G.S., Corr. Mem. University of Chile, &c. 



[Communicated by Prof. Owen, F.G.S.] 



[Abridged.] 



But few instances of the occurrence of fossil bones on the Western 

 side of the Andes J have been recorded. During my late visit to South 

 America, I made inquiries as to the existence of fossil bones in the 

 Isthmus of Darien, but I could not learn that any had been met 

 with, although railway-cuttings across the Isthmus were in progress § . 



Old Spanish writers speak of ^* bones of giants" having been 

 found at Manta, on the coast of the Pacific, 0° 59' S., 80° 40' W., 

 and at Punta St. Elena in 2° 1 1' south of the equator and also on the 

 Pacific II . Humboldt, from the information of others, states that 

 these bones are remains of great cetacean animals. 



South of this, in the desert plains of Tarapaca (19° to 22° S.), 



. * See above, pp. 284 & 288. f See above, p. 284. 



X Two species of Mastodon have been discovered on the Eastern side of the 

 Andes. The one {Mastodon Andium) has been met with in Peru, Chile, and 

 Tarija ; the other {M. Humboldtii) occurs in Buenos Ayres, Brazil, and Columbia ; 

 Cuvier's conjectural determination of these species was settled by Laurillard {Diet. 

 d'Hist. Nat. Art. Mastodon) and confirmed by Gervais ( Voyage de Castelnau). 



§ A notice of some fossil shells from the Panama Railway is given in Quart. 

 Journ. Geol. Soc. vol. ix. p. 132. — Edit. 



II Signor Osculati, an Italian naturalist, who visited South America in 1846-8 

 (' Esplorazioni,' &c., Milano, 1 vol. 4to), alludes to bones of Mastodon found near 

 Lake Papallacta, S.E. of Quito. 



