.IIHASMC CYCAPS FIJOM WYUMIXCJ. 2Ul 



Renault (('our. I5..1. I'oss., 1, pi. xii, fig. 3)." tliaii like eWhev Cycadeouica 

 ingcn.^ or Cycnddla nimautoxa. That is to say, the differeiu-es l)etween 

 tliese \-arious forms are not such as in themselv(^s ina>- l)e very readily 

 used for othei- than specific separations. Tli(> fact is also emphasized 

 that we are hei-e tlealing with a very generalized type of leaf structure. 



Bundle pattern of the petiole.— This IS IndlCatcd \\\ t llC VOUUg IcaVCS of C IJCd- 



(Iclhi ramcnto.^i and differs markedly from that of the living cycads. 

 It is nuich more fern-like in l;)eing arranged like a V with a ([uite 

 continuous xylem and phloem region. It is desired to cut some 

 further sections l)efore giving detailed figures. In PI. LXIII, I'lg. 1, 

 there is probably shown some distortion l)oth of tlie l)undle region 

 and of the transverse section of the petiole, due perhaps to desiccation 

 before the process of silicification began. The leaf represented in Fig. 1 

 of the same plate shows, in the uniform contraction between the veins 

 of the pinnules, what is quite likely an abnormality due to the same 

 cause. The bundle pattern of the petiole is not to be confused with 

 that of the leaf base. The latter, of course, merges into the former. 



Number of pinnules.— This has uot beeu determined, since it has not 

 l)een thought desirable to sacrifice any of these leaves by cutting 

 them in longitudinal section, especially since lumiber is scarcely of 

 specific value, varying often in the case of fronds from the same plant 

 and very greatly as a plant grows older and the relative size of its fronds 

 increases. The numloer in the present species may have been as low 

 as 30 or doubtless as high as 60. 



Form of the full-grown pinnule. — Thls uiay bc surmlsed with no small degree 

 of confidence. The fact that in the case of the frond shown in PI. 

 LXIII, Fig. 1, the number of bundles increases as successive pinnules 

 are cut, and then becomes constant, proves that the venation is 

 dichotomous after the manner of Zamia angustifolia Jacq., and shows 

 that the pinnules, though elongate, can not have had a broad base with 

 numerous veins like Dion, nor yet Hke Williamsonia gigas. (See PI. 

 LXII, Figs. 1 and 4.) The degree to which the tip may have been 

 acuminate and the relative width are of course not possible to deter- 

 mine from transverse sections alone. But undoubtedly the pinnules 

 of the present species presented an appearance quite like that of such 



a This figure is reproduced in Scott's Studies in Fossil Botany, p. 423, fig. 139A. 



