G. B. Wieland — American Fossil Cycads. 383 



Art. XLY. — A Study of Some American Fossil Cycads* 

 Part III. The Female Fructification of Cycadeoidea ; by 

 G. K. Wieland. (With Plates VIII-X.) 



Introduction. 



Female fruits of fossil Cycads from America have not been 

 hitherto described. European specimens, however, have fur- 

 nished two nearly perfect examples which have been made the 

 objects of careful research and discussion during the past thirty 

 years. In fact, the study of Bennettites Gibsonianus by 

 Carruthers, 3 and Solms-Laubach, 8, 9 together with Lignier's 12 

 investigation of Bennettites Morierie, may well be considered 

 one of the triumphs of modern paleobotany. As a result, the 

 structure of the cycadeoidean seed-bearing organs is nearly as 

 well known as that of the existing cycads. 



The subject of female fructification, as far as treated before 

 the announcement of the discovery of the corresponding male 

 flower in Part I of these contributions, has been amply 

 reviewed by Seward. Hence it is only necessary to state 

 briefly that the object of this preliminary paper is to deal with 

 several quite perfect cycadeoidean fruits as observed in cer- 

 tain trunks from the Jurassic of the Black Hills. These, it 

 will be seen, are in all essential characters similar to the 

 English, French, and Italian examples of Cycadeoidea, of which 

 the best known are Cycadeoidea ( Williamsonia) gigas, Car- 

 ruthers, and C. {Bennettites) Gibsonianus, Carr., both from 

 the lower Greensand of the Isle of Wight, C {Bennettites and 

 Williamsonia) Morierie, Saporta, from the Oxfordian of Nor- 

 mandy, and C. etrusca, Capellini and Solms-Laubach, from the 

 Etruscan Necropolis at Marzabotto, the original locality of 

 which is unknown. The American forms are so analogous to 

 the several foregoing species as to preclude more than specific 

 difference, and thus add one more argument in favor of the 

 approximately synchronous existence of these highly special- 

 ized forms on both continents. Whether or not final study will 

 permit their retention in a single genus is, however, a doubtful 

 question that need not now be taken up; nor can the subject of 

 the bracts and peduncles be treated in the present paper, 

 although recent studies by Scott 20 make it quite certain that 

 their investigation will furnish valuable data. 



* Part I of these studies appeared in this Journal for March of this year, and 

 Part II in the April number following. The numbers refer to the list of papers 

 given at the end of Part I. 



