226 Scientific Intelligence. 



age of the coal-seams. There is of course also a large amount of 

 local detail relating to the French coal-fields. 



On the whole, this memoir should be welcomed by all paleon- 

 tologists. It is undoubtedly most accurate- ami trustworthy as to 



- i if the c.. : ,l plant- which ihc author lias been able to 

 study in their various parts and organs; and in respect to all, it is 

 most suggestive, and cannot fail to lead to clearer views of the 

 whole subject. One conclusion which must strike every one, and 

 on which the writer of this notice has long insisted, is that the 

 arboreal vegetation of the Coal period must have been much more 

 varied than has been usually supposed; and that while we have 

 no doubt been instituting many unnecessary species for mere frag- 

 ments, we have on the other hand been forcing into unnatural 

 union very diverse forms, by trusting to merely external charac- 



2. Memoirs of the Geological Purvey of Kent.nr/cu. N. 8. 

 Mi.u.,,,:, Director. Vol. I, 334 pp. 4to. 187m— This first volume 

 of the Geological Survey of Kentucky, coi* 

 tain- four Memoirs. 



The first is on the Antiquity of the Caverns and Cavern life of 

 alley, and is by Prof. Shalek. We learn from it that 

 m the Mississippi valley, while the limestone of the Cincinnati 

 true caverns, far the larger part, and the 

 hngest, "ccur in the Subcarboniferous limestone. In Kentucky, 

 this innest.me has an average thickness of 150 feet and the cav- 

 erns are exceedingly numerous; the auihor slates that the length 

 ot the underground channels in this rock accessible to water is 

 thousands of miles; and he thinks it no overstate- 





say that there are at 1 



• these channels, the traveler may journey for fifty miles 

 ny parts of this limestone region in the wet season and 

 th no running water. In the history of the caverns a 

 of limestone has often held the streams for a long 

 n 1 thus a tier of caverns has been made; and then, this 

 " ii'-' won throuv.li, th< •-, ,; s ha d - < nded and com- 



sulted. Prof. Shaler observes that 



; ; ure of these caverns is the existence 6f great " domes" 



or wells which often rise in a single sweep from the lowermost to 



-r level of the caves ; a nd which are due to a fall in 



•;f an underground stream that originated in the early 



history of tin cum,,. Often , ••-,,< .1, • ,, , „_ r -1 W-M 



I'"- 1 "" t,! " vt -rtieal channel. ! .. and lofty 



d m. -. r„ r , of great caverns ah, , u .„,., , _ m !,,,[, ro mmunieat- 



ing with one another by the channel- and domes with streams 



<ora still pools to high waterfalls and using pebbles for 



ons, ai princij t i u nts of these 



" '- ■■-■ ■ - ' " ^ :■■ ■•• ■,: - :■ . ,-.; i!, 



,t. Shaler attributes to 

 us iiaving been forme remains. The great 



