﻿82 VEGETATIVE FEATURES. 



Later Count Solms says : 



"The only cycad, as far as I know, in which the stem with the leaves attached can 

 be determined with certainty, is Zamites gigas Morr. The specimen of this plant came 

 from the upper Jurassic sandstone of Yorkshire, and was obtained from its owner, 

 James Yates, for the Paris Museum, where I saw it. A figure of it is given by Saporta 

 (Plantes Jurassiques, vol. n, pi. 81). The stem bears a lateral bud enveloped in hand- 

 some leaves ; in this respect and in habit also it recalls Sta?igeria" (157, p. 94). 



Latterly, Seward has made a careful reexamination of the English cycadean 

 material. He also mentions, as follows, a Williamsonia specimen in the Paris 

 Museum, showing a stem with not only leaves, but the basal portion of a peduncle 

 attached, and evidently the specimen mentioned in the above quotation from Solms : 



"At the base we have a stem about 5 cm. broad, with the surface features indis- 

 tinctly preserved, but showing a number of imperfect scale leaves. To one side of 

 the stem, 5 cm. from the bottom of the specimen, are attached the petioles of two 

 clearly preserved fronds of Zamites gigas, and above these occurs part of a third frond 

 apparently in its natural position, but without the petiolar attachment. The stem is 

 prolonged obliquely upwards to the left in the form of a branch about 3 cm. broad and 

 14 cm. long. This branch is thickly clothed with hairy leaf scales and terminates in 

 numerous spreading leaf scales of a narrow linear-lanceolate form. The position and 

 surface features of this branch are very inadequately and incorrectly reproduced in 

 Saporta 's figure. If we now turn to the specimen figured by the same author as a 

 peduncle of Williamsonia (Saporta, Pal. Franc. Plant. Jurass., vol. n, p. 55), and which 

 terminates in what appears to be a closed Williamsonian inflorescence, we find the 

 characters are identical with those of the branch of the stem bearing Zamites fronds. 

 Specimens of peduncles in the British Museum, and others in the collections of Whitby 

 and Scarborough, afford similar proof of the identity of the detached peduncles and 

 the obliquely placed branch of the leaf-bearing stem. There can be little doubt that 

 the terminal bud-like structure on these peduncles is a young and unexpanded William- 

 sonia, but even if this be disputed, there can be no question as to the identity of the 

 typical Williatnsonia scale leaves and those of the terminal bud on the peduncles' ' (145). 



Considering the great number and variety of " cycadophytes," this scantiness 

 of direct evidence as to the connection of stem and leaf as shown in the foregoing 

 review is striking indeed ; but all the more satisfactory, from both the biologic and 

 taxonomic viewpoint, has been the writer's discovery that many of the silicified 

 cycad trunks from the Black Hills and Wyoming bear wonderfully preserved crowns 

 of prefoliate to partially emergent young leaves, as well as occasional isolated or 

 adventitious leaves, the cell structure in most instances being indicated in great 

 detail. 



The first description given of a crown of silicified leaves was based on that 

 borne by the type of Cycadeoidea t'ngeus, which, as elsewhere noted, likewise fur- 

 nished the first evidence as to the true character of microsporangiate fructification in 

 the fossil cycads (188). Later the leaves of Cycadella rametitosa, one of the fine 

 series of silicified trunks from the Freezeout Hills of Wyoming, were figured and 

 briefly described by the writer for Ward's Status of the Mesozoic Floras (194). 



