1^0.2.] SCUDDER ON PALEONTOLOGY OF FLORISSANT, COLORADO. 299 



The testimony of the few fishes to the climate of the time is not unlike 

 that of the plants, suggesting a climate, as Professor Cope informs me, 

 like that at present found in latitude 35° in the United States ; while 

 the insects, from which, when they are completely studied, we may cer- 

 tainly draw more definite conclusions, appear from their general ensem- 

 ble to prove a somewhat warmer climate. White ants are essentially 

 a tropical family, only one or two out of eighty known species occurring 

 north of latitude 40°. In North America only three have been recorded 

 north of the border of the Gulf of Mexico, excepting on the Pacific coast, 

 where one or two more extend as far as San Francisco. Two species, 

 both belonging to the second section, are found in the valleys below 

 Florissant, in 39° north latitude. Florissant itself is situated 2,500 

 meters above the sea, and the presence of so considerable a number of 

 white ants embedded in its shales is indicative of a much warmer climate 

 at the time of their entombment than the locality now enjoys. Investi- 

 gation of other forms increases the weight of this evidence at every 

 step, for nearly all the species (very few, certainly, as yet) which have 

 been carefully studied are found to be tropical or subtropical in nature. 

 As, however, most of those studied have been selected for some strik- 

 ing feature, too much weight should not be given to this evidence. 



As noted above, the superabundance of specimens of single species 

 of plants (Planera and Myrica) is repeated in the insects, Avhere certain 

 species of Formicidae among Hymenoptera, of Bibionidae among Dip- 

 tera, of Oercopida and of Alydina among Hemiptera are to be counted 

 by fifties and hundreds. 



The only other general feature which may already be noted among 

 the insects is an unexpected paucity of aquatic larvae or the imagos of 

 water-insects. Hardly a dozen neuropterous larvae have come to hand, 

 very few aquatic Hemiptera in any stage, and of Hydrophilidae and other 

 water-beetles no great number. The paucity of neuropterous larvae is 

 the more remarkable from the abundance of Phryganidae, while not a 

 a single larva-case has been found. 



As to the age of these deposits, the opinions of Mr. Lesquereux, based 

 on the study of tertiary plants, and of Professor Cope, drawn from his 

 knowledge of tertiary fishes, are far more harmonious than one would 

 expect from their known divergence of view concerning the testimony 

 of the fossils to the age of other tertiary beds in the West. Such dis- 

 parity of ideas did hold at first, Mr. Lesquereux maintaining in his ear- 

 lier notices of the flora the probability of its later miocene age ; in the 

 Tertiary Flora he placed it in the "Upper Green Kiver" di^ision of his 

 "fourth group," together with the flora of Elko, Nev., the Green River 

 beds being placed directly beneath them. In Haydeu's report for 1876 

 he refers the Florissant deposits to the upper miocene. In his review 

 of Saporta's Monde des Plantes,* while still considering it as mioceue, 

 he points out certain important relations which it bears to the flora of 



*Am. Journ. Sc. (3), xvii, 279. 



