﻿1 8 INTRODUCTORY. 



as the present wholly valuable inferences may be made only from associated stems, 

 leaves, and fruits, if preceded by exact field work in all the important localities — 

 the prime necessity in all cases, and the fountain head whence alone our knowledge 

 of extinct florae may derive that completeness which is of Anal and intrinsic value. 

 We need not, however, go beyond the present group to show that important infer- 

 ences may be drawn from associated stems, leaves, and fruits, if the evidence at 

 hand is simply presented or considered with care. However loath botanists were 

 for many years to accept as fairly correct the restoration of Williamsonia gzgas, 

 it must uow be admitted that here is an instance in which association led to correct 

 inference. That much may be done in the case of dissociated parts of the more 

 highly organized plants, towards learning which are portions of one and the same 

 plant, if careful work is done in the field by competent workers, is a fact to bear in 

 mind. For, each additional pre-Tertiary plant we learn to know by stem, leaves, and 

 fruit has, biologically speaking, an immense value. 



Having mentioned the principal cycad localities known, it may not be amiss to 

 point out very briefly how great is the additional field concerning which we as yet 

 know nothing, and from which it is to be hoped that valuable supplementary mate- 

 rial may yet be obtained. In central North America, which has yielded the most 

 and the best-silicified trunks, scarcely a third of the Rocky Mountain slope has been 

 adequately explored, perhaps not a fifth. But as a large reward of initial exjDlora- 

 tion the barrier islands of Antarctica have already yielded cycad and other florae, 

 paralleling the extinct plant life of Greenland and of like marvelous interest. Con- 

 cerning the western slopes of the Andes we know exceedingly little, some Jurassic 

 plants having been reported from Patagonia. Of the slopes of the great mountain 

 chains of Asia we know nothing. And of the countless fossil plants of which 

 science has to learn from Africa, Australia, and the great wastes facing the Arctic 

 Ocean, but few or no tidings have yet come. Truly, paleobotany is yet young, and 

 its most successful votary must yet be the field-worker and the explorer. 



OLD-WORLD TYPES OF CYCADEOIDEAE. THE HORIZONS IN WHICH THEY OCCUR, AND THE 

 MUSEUMS IN WHICH THEY ARE LOCATED. 



In the following general list of Old World cycads it is the purpose rather to 

 give only those forms which are either very well known and structurally important, 

 or that have especial value in studying the general character of evolution in the 

 group. Such genera as Draazna II ~/t/ia»iia, Becklesia, Dichopteris^ with little or 

 no structure preserved and of doubtful cycadean affinity, are mostly omitted. 



Scaly Clays of Italy. Types, with Date of Discovery. (From Capellini. ) 



1745. Cycadeoidea Montiana Capellini & Solms. Lapideorum balanorum, congeries insignis, Monti. 



Rio della Cavaliera, Bolognese. Figured by Monti (1753). The type has been lost. 



1825. C. intermedia Ranzani. Fiume Reno, Bolognese. Museo geologico di Bologna. 



1849. C. Scare/belli Meneghini. Fiume Sauterno, Imolese. Musei d'lmola e Pisa. 



1850. C. Pirazzoliana Massalongo. Torrente Correchio, Imolese. Museo geologico di Bologna. 

 1852. C. Bianconiana Massalongo. Torrente Samoggia, Bolognese. Museo geologico di Bologna. 

 1859. C. veronensis Massalongo. Veronese? Museo civico di Verona. 



