Geology and Mineralogy. 231 



Mr. Heilprin's report describes the features of the region visited, 

 its geology, and its paleontology, besides making some contribu- 

 tions to its zoology. Seventeen of the twenty plates are covered 

 with admirable autoglyphic figures of the fossils ; and besides 

 these, the snake Tropidonotus taxispilotus is figured on plate 17; 

 the fish Ictalurus Okeechohe'dnsis on plate 18, and the new species 

 of Aplysia, A. Willcoxi, on plate 19. 



A history of former geological investigations in Florida is given 

 which includes a notice of Conrad's identification of the Vicks- 

 burg Tertiary at Tampa Bay ; an account of the work of Dr. E. 

 A. Smith, geologist of Alabama, who found a considerable part 

 of the northern half of Florida to be underlaid by a fossiliferous 

 limestone, whose fossils were studied by Mr. Heilprin and referred 

 to the Oligocene, and found to include, besides great numbers of 

 Orbitoides complanata, the first then recognized of American 

 Nummulites, named N. 'Willcoxi,' and Dr. J. C. Neil's discovery 

 of Mammalian remains, near Archer, in Alachua county, Florida, 

 among which Dr. Leidy recognized species of Mastodon, Rhino- 

 ceros, Tapir, Horse, Llama, Camel and Hog. The results of the 

 explorations made are then given, with the following general con- 

 clusions. 



The surface rocks of Florida are exclusively Tertiary and Qua- 

 ternary. No observed facts sustain the coral theory of formation 

 propounded by Agassiz ; on the contrary, they prove that the 

 coral tract of Florida is confined to a border region on the south 

 and southeast ; that the few fossil corals found in Tertiary depos- 

 its are sporadic growths, not parts of reef formations. The forma- 

 tions represented are the Oligocene, Miocene, Pliocene and Post- 

 pliocene, which, commencing with the oldest at the north, follow 

 one another in regular succession from north to south, thus clearly 

 indicating the course of progress in the growth of the Peninsula. 

 The successive belts are not directly east and west in course, but 

 to the eastward are deflected northeastward so as to conform 

 approximately to the Atlantic border. No Eocene rocks were 

 found, but such may exist in the northern section of the State, 

 and possibly they may comprise part of what is called Oligocene. 

 The different formations are horizontal or very nearly so ; and 

 they follow one another without any broad or distinct lines of 

 faunal separation. The northern half of Florida appears to be 

 covered with a deep-sea formation, and the southern with beds 

 made in a comparatively shallow sea. The elevation of the area, 

 especially the southern part, went on very gradually, without 

 leaving any marks of disturbance. Before the elevation was com- 

 pleted, a large part, especially the southern, was a submerged flat 

 or plain, the shallow coverings which were favorably situated for 

 a profusion of animal life, and " the accumulation of reef struct- 

 ures and of vast oyster and scallop banks ;" and freshwater streams 

 existed as is proved by the commingling of marine and fluviatile 

 mollusks in the deposits of the Caloosahatchie. The derivation of 

 the modern species of the coast from older Florida species is easily 

 traced out. 



