354 Linnean Society. [Dec. 19, 



rocks which succeeds (Keuper.Bnnter-Sandstein, Muschelkalk, Lias- 

 Jura, and Wealden formation), none have been collected except 

 three species in the Cretaceous formation, especially in Quadersand- 

 stein. The greatest number has been found in the Tertiary class of 

 rocks, viz. sixty ; twenty-nine of which belong to the Eocene system, 

 and thirty-one to the Miocene formation. The habitat of nine spe- 

 cies is unknown. 



"It will be seen from this synopsis that there was a geological 

 period when Palms were entirely wanting in the extinct flora, or 

 when, after their first appearance on the globe, they vanished again, 

 and after a lapse of time reappeared ; a state of things, which if 

 confirmed by future investigations, would certainly be highly curious, 

 and is one never before observed in a like manner in any large group 

 of plants. No species is common to two formations. Several spe- 

 cies show a remarkable degree of resemblance with those of the 

 flora now existing, especially some of those collected by Junghuhn 

 in Java, as for instance, Amesoneuron calyptro- calyx, Gopp., A.dra- 

 cophyllum, Gopp., A.fagifolium, Gopp., and A. anceps, Gopp. But 

 it would be rather bold, perhaps injudicious, to attempt identifying 

 them, from the fragments hitherto collected, with those of the pre- 

 sent flora. The results hitherto obtained only entitle us to say, — 

 Palms make no exception to the rule generally received, that the 

 laws governing the vegetable kingdom were the same in all periods 

 of our earth's history when plants existed ; and that the species of 

 Palms have a very local geological, as they have a very local geo- 

 graphical distribution." 



Read also. Extracts from a Letter addressed to Sir W. J. Hooker, 

 F.R.S.. F.L.S. &c. By Richard Spruce, Esq. Dated St. Carlos de 

 Rio Negro, Venezuela, March 19, 1854. This letter is intended for 

 publication in Sir W.J. Hooker's ' Journal of Botany.' 



December 19, 1854. 

 Thomas Bell, Esq., President, in the Chair. 

 Isaac Newton Loomis, Esq., M.D., was elected a Fellow. 



Read a Memoir " On the Food of certain Gregarious Fishes." By 

 Robert Knox, Esq., M.D. Communicated by William Yarrell, Esq., 

 V.P.L.S. 



Dr. Knox's inquiries were commenced about thirty years ago, and 



