sterile bracts. He described the bundle of each bract as 
‘*protostele-like,’> having protoxylem in the center of the 
xylem mass. The seed is described as being terminal, 
erect and provided with a single integument. 
Florin has shown conclusively in this paper that the 
ovulate strobilus of Cordaianthus and that of the extinct 
Carboniferous and Permian conifers of the Walchia type 
are fundamentally alike. In deference to Doctor Florin, 
who only preliminarily published and provisionally de- 
scribed these groups, I make no attempt to draw gener- 
alizations from the Iowa specimens, beyond the concept 
of the species. 
The male fructifications have usually been described, 
following Renault, as a thick axis bearing spirally ar- 
ranged bracts with the sex organs inserted between them. 
A number of nominal species have been named from 
structurally preserved specimens. The best known ‘‘spe- 
cies’? is Cordaianthus penjont Renault. In this form the 
stamens are spirally arranged and are inserted between 
robust, woody, acicular bracts. It is probable that the 
stamen is a fertile bract. Each ‘‘stamen’’ consists of a 
sporophyll (not a filament) upon which are borne six (one 
tosix) elongate pollen-sacs (7). Pollen of this species and 
of another, Cordaianthus saportanus Renault, have been 
observed. They are ellipsoidal, approximately 0.09 mm. 
<0.05 mm., and have extensive gametophytic tissue 
within the intine. The number of cells often exceeds 
thirty. Renault originally described them as having ten 
to twenty equivalent cells. 
The strobilus, at any rate, is a simple structure some- 
times interpreted as a ‘“‘mixture of sterile and fertile mi- 
crosporophylls.’’ Renault described the staminate strob- 
ilus as being extremely simple, formed of only a few 
stamens. He believed that the entire structure was a 
flower. Solms-Laubach (21), later, interpreted the ‘‘sta- 
Ena 
