﻿9 6 



VEGETATIVE FEATURES. 



the plant had been grazed upon by some animal or had been otherwise injured 

 and was attempting to recover itself. 



In all the sections, whether naturally or artificially polished, the bundle system 

 is fairly well indicated by natural iron-oxide staining as well as other features of the 

 leaf. It is specially to be noted that the sections all apparently lie above the summit 

 of the rachis. It will be recalled that in the crown of leaves borne by Yale cycad 

 ioo, several leaves are present which may have emerged one or more feet above the 

 summit of the trunk, so that only basal pinnules remained unexpanded. 



The bundle system indicated by the present transverse sections of folded young 

 leaves of trunk 208, together with that of several similar leaves of C. ingens (type), 

 next follows. 



Number of Vascular Bundles Counted in the Blades of Successive Pinnules in 

 Transverse Sections of Various Prefoliate Leaves of Cvcadeoidea ingens 

 (type) and C. ingens (Trunk 208). 



No. of 

 pin- 

 nule. 



2 

 3 



4 

 5 

 6 



7 

 8 



9 



10 

 11 

 12 

 13 

 M 

 1 5 

 16 



J 7 

 18 



19 

 20 



21 

 22 

 23 

 24 

 25 

 26 



27 

 28 

 29 

 3° 

 31 

 32 



(a) Cycadeoidea in- 

 gens (type). 



I II III 



(S. 46). (S.169). (S.170). 



3 

 7 

 8 



9 

 11 



13 

 13 

 12 

 12 

 13 

 13 

 13 

 13 

 13 

 14 

 14 

 11 



9 



3 



5 



7 



9 



9 



10 



11 



11 



13 



14 



17 



J 7 



17 



17 



18 



20 



!7 



18 

 16 



20 

 20 



20 

 20 



17 

 16 



1 5 



14 



12 



12 



9 



7 



5 



17 

 22 



24 

 25 

 25 

 25 

 25 



(a) Cycadeoidea ingens, type specimen : 



I. From tip of one of the younger leaves of crown. 

 Dimensions of section 1.25 cm. in tangential 

 by 1.60 cm. in radial direction. Pinnule tips 

 cut both proximally and distally. (S. No. 46.) 

 II. Parallel to and 3 cm. beneath, that is, proximal 

 to preceding , but also passing above tip of 

 rachis. (S. No. 169, photograph 3, plate xix.) 



III. Larger leaf than either of the preceding, in 

 which the rachis is cut and has a vertical 

 thickness of 1 cm. Only the basal pinnules 

 are non-emergent and traversed by the section, 

 the remainder having grown out beyond the 

 armor and failed of preservation. Both rachis 

 and petiole have begun to elongate. (S. No. 

 170, shown in photograph 6, plate xxi.) 



(b) Cycadeoidea ingens (cotype T. 208) : 



IV. Adventitious leaf borne 43 cm. above base of 



trunk. Horizontal width of transverse section 

 1.5 cm. Vertical height 1.4 cm. This section 

 was naturally polished in place on the trunk 

 and passes well above tip of rachis. (Photo- 

 graphed on plate xix.) 

 V. Naturally polished transverse section of adven- 

 titious frond with transverse measure 1.3 cm. 

 and vertical measure of 2 cm. (Photograph 

 7, plate xix.) 

 VI. Section of leaf polished in natural position on 

 trunk. Pinnules are the largest yet observed 

 in any of the young leaves. Section passes 

 above tip of rachis. (Photographs, plate xix.) 



It is evident that the several leaves of Cycadeoidea ingens, as seen in trunk 208, 

 represent varying stages of growth, with the exception of Nos. 5 and 6, which are 

 in almost identically the same stage of development. A study of the leaf expansion 

 of the several species of Macrozamia may readily be made and will perhaps more 

 exactly than in the case of any other genus furnish interesting comparative data. 

 The slight increase in the number of bundles in leaf No. 6, notwithstanding its 



