﻿YOUNG FRUCTIFICATION'S. 



18- 



FRU1T V. 



Iii figure ioo and plate XL there is shown the largest of the present series of 

 ovulate strobili. This fine fruit was borne near the summit of the trunk, and is 



St99 



Fig. 99. — Cycadeoidea dacotensis. T. 214. Fruit II. S. 490. Natural size. Longitudinal section through an ovu- 

 late strobilus. More compressed and conical than No. V of this same trunk and probably somewhat younger. 

 At d are remains of an hypogynous disk as in all ovulate cones of C. dacotensis — in the present fructification rather more distinct than usual, 

 c. c. Outer border of cortical parenchyma, on which are seated the leaf and peduncle bases -hence the true surface of trunk. 



Fig. 100. — Cycadeoidea dacotensis. S. 499. Fruit V. T. 214. Natural size. Longitudinal section through ovu- 

 late strobilus, with surrounding bracts and leal bases. (C(. photographic series, PI. XL.) 



I-VI denote the successive levels of the transverse sections shown in figure 100 continued, z. Line marking the probable insertion of 

 the seed stems and interseminal scales; s, basal portions of hypogynous disk, doubtless staminate and matured some time previous 

 to fossilization ; a, axillary leaf base ; I, a leaf trace ; c. the bundle cylinder of the peduncle. The arrow points toward superior 

 side, the section having been cut in a quite exactly radial longitudinal plane of the trunk ; also that the bracts (as shown in 

 solid black) are cut throughout their entire length on both sides of the fruit. This section is perfectly oriented and of rare beauty. 



wholly symmetrical. It is of special importance as bridging the gap between the 

 younger elongate conical forms and older robust pear-shaped forms with much 

 larger ovules, as borne on other trunks. The seed-stem zone is not distinct, but 

 preservation zones indicate its greatest thickness as 5 mm., or a very little greater 

 than in fruit 11. The present cone is one of the nearest of all to the summit of the 

 trunk, and about its base are the usual traces of the earlier presence of an envel- 

 oping hypogynously borne disk. 



