﻿YOUNG FRUCTIFICATION'S. 



'73 



of silicificd cycads. But when in its presence there is — to say nothing 

 of the time required — a limit to one's wish to drill and cut, even by the perfected 

 methods now available. The main facts thus far derived from the study of the 

 young fruits and trunk features of C. superba follow in resume. 



(a) The central trunk early gave rise to four lateral branches, all of which 

 developed at a rapid and nearly equal rate. 



{b) The spiral succession of the leaf bases has been disturbed only by the 

 appearance of the fifty-three young axillary fructifications distributed sparsely and 

 about equally over the central trunk and its four branches ; and most of the fruits 

 or even all belong to the same prefloral stage. Only one or two are at all advanced 

 iir growth, and but a few remain very small. Three seasons of fruit growth are 

 hence the most that can possibly be predicated, although most, if not all, of the 

 fruits seem to be those of a single season. 



(f) The only young fruit cut yielding good structure in thin section (though 

 most of the fruits must be well preserved) is certainly of the usual disk-bearing 

 cycadeoidean type. 



(</) Two other fruits not cut are known to be ovulate. One is small, but like 

 the young axes studied in serial section may have early borne an hypogynous 



staminate disk function- 

 ally microsporangiate or 

 not. The other is of con- 

 siderable size and might 

 perchance have borne 

 pollen a season earlier 

 than would the young 

 disk-bearing axis had 

 fossilization not inter- 

 vened. 



ii 



Fig. 92. — Longitudinal and transverse sections o( young fructifications of Cyca- 

 deoidea. ■' 4. The longitudinal section (I) shows no outer disk, though the 

 plainly indicated seed zone appears to be even younger than that shown in II , 

 where there is a distinct outer disk. Both ovulate cones are, however, in a 

 very early stage of growth, the seed pedicels being without elongation. 



(V) The presence of 

 a bisexual floral type is 

 the more probable, but 



degrees of moncecism or dicecism may be present. The actual condition in this 

 respect is only inferred. 



(_/) The sparse number of fruits present may indicate, considering the present 

 trunk alone, that the production of fruits would normally have extended over a 

 considerable time, or else that fructification would have been followed by rest and 

 other fruiting seasons. Or it may also be that the fruits actually present are the 

 only ones that would in any case have been produced, since the greater number 

 are in nearly the same stage of growth. 



It may be well to mention here that had the basal portion of the largest ovu- 

 late strobilus borne by C. superba (type) been detached with its surrounding bracts 

 and preserved as an imprint, or, better, as a cast, it would have presented very 



