﻿1 86 REPRODUCTIVE STRUCTURES. 



THE PULCHERRIMA STAGE OF TRUNK-GROWTH. 



If it be true that many trunks, as in the case of No. 214, never produced a 

 series of fruits until reaching a large size, then among the large collections of 

 cycads at hand there should be some trunks of considerable size of the same or 

 closely related species that bear no fructifications, and others that bear only young 

 or, at most, but a very few well-advanced fructifications. In either of these cases 

 there will be but little disturbance of the spiral succession of the leaf bases, owing 

 to the emergence of the large axillary fruits ; and consequently far more regular 

 and ornate appearance will be presented than later in life, when in full fructifica- 

 tion. Now, such stages are found to be well illustrated if one compares a sufficient 

 number of trunks. The immense branching specimen on exhibition in the Yale 

 University Museum, numbered 300, and the largest of its kind known {if. plate xn), 

 bears a considerable number of young fruits, though no earlier fruits than these 

 appear ever to have been borne by any of the branches. As a result, the leaf-base 

 spirals are still of pronounced regularity, and the same is even more conspicuously 

 true of several of the trunks shown on plate v, notably trunk 741, photograph 1. 

 Also to several very perfect and quite similar low-growing trunks of the branching 

 type seen in C. dacotensis and C. Marshiana the specific name C. pulcherrima 

 has been given. This species is, however, not a valid one, and is simply based on 

 younger trunks of the several foregoing types, in which the helicoid arrangement of 

 the leaf bases is undisturbed. The type of C. pulcherrima is in the United States 

 National Museum collection, and is figured by Professor Ward (138, plate lxxx). 

 It is a most beautiful specimen, bearing a few isolated young fruits and various 

 branches, while the arrangement of the leaf bases presents an undisturbed and strik- 

 ing regularity. But, plainly, these are only individual peculiarities and not in 

 themselves true specific characters of young Cycadeoidece. The trunk is simply a 

 younger specimen of C. dacotensis, and, had its growth continued, would have 

 formed the central member of a clump. Being already quite large, it was rapidly 

 approaching its main period of fruit production when fossilized. This condition 

 of robust growth and undisturbed regularity of leaf bases may be appropriately 

 termed the pulcherrima stage of trunk-growth and fructification. 



