﻿108 REPRODUCTIVE STRUCTURES. 



many instances preserved in unrivaled perfection and exhibiting many important 

 features hitherto unknown, together with complete habitus details. On the basis 

 of this newly discovered material, observations on general habits of growth were 

 added, and it was shown that the fruits of several of the Black Hills species were 

 very closely related to the English and French species, B. Gibsonianns and B. Mor- 

 ierei, thus further illustrating the cosmopolitan distribution of the Cycadeoidese. 

 Still more recently Scott has given, in his Studies in Fossil Botany, a compact and 

 excellent description based in the first place on Benncttites Gibsonianus (135). 



It has already been remarked that the great essential for the preservation of 

 these cycadean fruits in organic connection with the parent plant is that they 

 shall not be protruded much beyond the protecting armor of leaf bases before reach- 

 ing a fairly mature stage of growth. The ovulate fruits of the closely related 

 English Bennettiies Gibsonianus, the French B. Moricrei, and the American Cycad- 

 eoidea U'ielandi, etc., meet this requirement more nearly than in the case of any 

 others yet discovered ; and for this reason among the specimens from the Black 

 Hills mature or nearly mature fruits of this type are more frequent than in the case 

 of other species. There are, I may say, hundreds of examples of nearly full-sized 

 strobili, while those of other species borne on longer peduncles, and hence usually 

 preserved, if at all, in a less mature stage of growth, are less frequent. It appears 

 possible that in some cases staminate flowers must, on the contrary, have been borne 

 on rather long peduncles. In any such instances partial or but scanty evidence of 

 fruits may be expected, as the main portion of the inflorescence would project 

 beyond the zone of preservation. Habits of growth very favorable to preservation 

 are to be seen in C. dacotensis with heavy armor and short peduncles. In this 

 species, despite the far shorter period of the year during which male flowers present 

 a stage of development favorable to preservation, a considerable number of such 

 axes in the unexpanded condition are preserved, with only a minor number of the 

 well-developed and entire ovulate fruits, though younger forms are frequent. 



By far the best examples of fertile trunks from the Black Hills bearing finely 

 preserved and numerous ovulate fruits have been referred by Professor Ward to C. 

 Wielandi. Our consideration of ovulate fructification in the American cycads 

 will hence begin with the fruits of this species. Following, other types closely 

 allied, but differing in various features, will be described. 



THE OVULATE CONE OF CYCADEOIDEA WIELANDI WARD. 

 (Plates XXI-XXIII.) 



The splendidly preserved trunk 393 of the Yale collection is in all respects 

 strikingly similar to the type of the present species (Yale cycad 77), and has already 

 received extended notice in connection with the subject of trunk structure. As the 

 specimen had been originally broken into several pieces, a half dozen of the quite 

 mature fruits it bears were the more readily removed for study, and afforded the 

 main material for the following description. 



