384 G. R. Wieland — American Fossil Cycads. 



The Fruit of Cycadeoidea Wielandi, Ward (MS.). $ 



General Features. — Cycadean trunk No. 77 of the Yale 

 collection, illustrated on Plate VIII, figure 1, is the female type 

 of the foregoing species. It is a finely preserved example, bear- 

 ing laterally, in addition to ten apparently fresh scars left by 

 the shedding of ripened fruits, forty more or less complete 

 seed-covered fruits, which were mature or nearly so when 

 fossilization began. The shape of these fruits is ovoid, and 

 their average size is from 3*5 to 4 cm in length by 2 to 2'5 cm in 

 diameter. In both size and form, they resemble the fruit of 

 Cycadeoidea (Bennettites) Gibsonianus, Carr., though the 

 seeds are less elongate in the latter species. 



The embryos of the seeds of this trunk prove to be the only 

 important structures not present in unusual clearness of detail. 

 Moreover, this was the first seed-bearing cycad to be described 

 as such from American formations, as well as the one upon 

 which these studies were begun. Hence it is made the first 

 type of female fructification in American cycads, although 

 other more perfect supplementary material has since been 

 studied. 



A close examination of the specimens represented in the 

 plate affords interesting facts concerning the fruit-bearing 

 habit of Cycadeoidea. In their various stages of growth, 

 maturity, and dehiscence, the fruits are borne on short pedun- 

 cles approximately of the same length, thus indicating that the 

 mature fruit was not protruded further from the trunk by 

 subsequent growth. Nor does there seem to be any order of 

 maturity from the base to summit of the trunk in either 

 direction. 



In several other related trunks most of the fruits have been 

 shed, being represented by scars only ; while a few floral axes 

 remain undeveloped or in an atrophied condition. Still other 

 trunks of this and associated species are barren or bear embry- 

 onic fruits. The latter condition is of considerable importance, 

 as it will permit a developmental study of the organs. The 

 only general conclusion to be drawn at present, however, is 

 that there was no sharply limited period when these cycads 

 matured their flowers. . Apparently there was a progressive 

 maturity of fruits through an entire season, which was followed 

 by several seasons of unfruitfulness. 



From the characteristic form and sculpturing of the scars 

 representing the position of the matured fruits, it would seem 

 that the latter were shed by the parent plant with their parts 

 intact and often with few or no accompanying bracts. 



Following fructification and the shedding of ripened fruit, 

 there was a closing up of bracts about the receptacle, with 



