51 



mixed state the salt uniformly exists. In pi-ecipitates produced 

 in boiling sea-water, and in our analyses, we estimate the phos- 

 phoric acid as a bone-phosphate salt, which is not sti'ictly a 

 coi-rect statement. The results here given allow us to readily 

 explain by simple solution and evaporation the conversion of the 

 granular and finely divided fish bones into a solid, compact rock, 

 Avhere all traces of its granular form are lost. 



The President gave an account of some fossil bones collected 

 in Texas. For these the Society is indebted to the liberality of 

 Dr. Charles Martin, Surgeon U. S. Navy. They were pur- 

 chased by him while attached to the Coast Survey dui-ing the 

 winter of 1 855-5 G, at the mouth of the Brazos River. They 

 were discovered in the bed of the river, during its low stage, 

 about fifty miles from the coast. The collection is very valuable 

 and interesting, not only as representing three distinct races of 

 gigantic quadrupeds, but as indicating a new locality in the 

 geographical distribution of the animals to which they belonged. 

 It is not a little remarkable that three such genera as Mastodon, 

 Elephant, and Megatherium, should be represented in a collection 

 of no more than eight specimens taken at random. Six of the 

 eight appear to have undergone similar changes of density and 

 mineralization ; these are the Symphysis of the lower jaw, an 

 ultimate Molar, and the Femur of an Elephant, the Tibia of 

 Megatherium, and the two Molars of a Mastodon. The others 

 are lighter colored, and much less dense. Coming as they do 

 from the bed of a river, it is impossible to determine how far 

 they were originally associated in the same geological formation. 

 It is not impossible that those first mentioned were from the 

 same locality. 



1. Symphysis of the lower jaxo of cm Elephant. — The branches 

 of the jaw were broken ofi" on both sides ; that of the right a 

 little in advance of the alveolus, and that of the left just at the 

 alveolus. The fragments of the branches now remaining form 

 an open angle of about 112'^ to 115'^. The depth of the sym- 

 physis on its inner face is about five inches. The channel or 

 groove which is continued over the upper border of the jaw on 

 the median line, and descends towards the chin in front, is quite 

 short and reaches but little below the upper edge of the jaw. 



