1847.] Association of Geologists and Jfaturalists. 211 



concretibility and the storehouse of fat was laid up, upon which 

 the animal subsisted when digestion was extinguished. 



There is nothing in the habits of hibernating animals to dis- 

 tinguish them, for their habits vary in different countries. Hiber- 

 nation may depend on a difference of temperature. Lizards hi- 

 bernate in France and do not in the Island of Santa Cruz. 



The immediate causes of torpidity are cold, drought, want 

 of oxygen and necessity for repose. 



Dr. J. C. Warren expressed his gratification at the remarks 

 made by Mr. Browne: He said that the use of the omentum, 

 about which there had long been a difference of opinion, was to 

 afford a soft cushion for the sensitive intestines, which are always 

 put in pain by pressure. It may also serve as a reservoir for food 

 when the animal is not In a state to digest it. In fevers and con- 

 sumption the fat is taken up by the absorbent vessels to supply 

 the want of food. The Doctor's impression was, that hibernation 

 was the result of cold acting on the nervous system, and through 

 this system paralyzing all other parts of the body. 



Professor Agassiz did not agree with Mr. Browne upon the 

 point of the cessation of circulation during hibernation. He ask- 

 ed what experiments had been made to test this point? Mr. 

 Browne replied, that a French naturalist, Mr. Sacy, who had in- 

 vestigated the subject, had made a thousand experiments. Mr. 

 Browne had added upwards of forty upon reptiles. Professor 

 Agassiz was of the opinion, that until the membrane of the wings 

 of bats in a torpid state had been examined by a microscope, to 

 see whether the blood circulates, it was not proper to pronounce 

 decisively that circulation ceases. He was further of the opinion 

 that until it has been shown that the species of lizards in France 

 and Santa Cruz were identical, it would not do to assert that hi- 

 bernation depends on the difference of climate. 



Remarks were also made by Mr. S. S. Haldeman of Carlisle, 

 Pa., and Dr. Samuel Jackson of Philadelphia. The latter gen- 

 tlemen expressed the opinion that respiration was not entirely 

 suspended. Professor Agassiz stated that a friend was investiga- 

 ting most minutely the subject of the hibernation of the dormouse, 

 at Nuefchatel. 



Dr. F. Roemer of Berlin, Prussia, made a report on the results 

 of a geological tour recently made in Texas. The fossils of the 

 corresponding formation of the old and new world were compar- 

 ed, and reference was made to their geograpical distribution. He 

 had ascertained that the isothermal lines of the cretaceous epoch 

 (as indicated by the fossils) were the same on the two continents 

 of Europe and America, as at the actual epoch. 



Professor S. S. Haldeman presented an interesting fact in the 

 geograpical distribution of animals. He stated that an insect was 



