116 EvaNs: TAXILEJEUNEA PTEROGONIA 
considerable range of variation. Fic. 9 illustrates the first 
involucre of a branch-system taken from a Peruvian specimen and 
brings out the fact that there is a slight coalescence between the 
bracteole and the bracts and also between the bracts themselves. 
In the bract on the left the basal tooth represents the lobule but 
the next tooth is even larger and more sharply pointed; the other 
teeth are much smaller, several of them being nothing more than 
projecting cells. The other bract shows similar teeth, the lobule 
(the basal tooth) being much like the others; the bracteole is 
unidentate on each side. Fics. 10-12 illustrate the bracts and 
bracteole of the second inflorescence of the same branch-system ; 
Fic. 13, the bracts and bracteole of the first inflorescence of 
another branch-system from the same material; Fics. 14 and 15, 
one bract and the bracteole of the second inflorescence of this 
second branch-system; and Fics. 16-18, the bracts and bracteole 
of an inflorescence taken from a Jamaican specimen. It is not 
necessary to describe these in detail, but the unusually large 
lobule in the left-hand bract of Fic. 13 should be noted and also 
the approach to an entire condition shown in Fic. 17. There is 
perhaps a tendency for the first inflorescence of a system to develop 
more strongly dentate bracts with larger lobules than the succeed- 
ing inflorescence or inflorescences, but this tendency is too vague to 
be insisted upon. Bracts which are absolutely toothless and which 
show scarcely a sign of a lobule occasionally occur (although 
none are figured); they are commonly associated with the second 
or third inflorescence of a systen, but even the first maioresornce 
sometimes shows bracts of this character. 
The perianth is characterized by the dentate to spinose wings 
borne on its five sharp keels (Fics. 1, 2 and 19). These wings 
may be either continuous or once or twice interrupted and rarely 
exceed ten cells in length or three in width; sometimes a second 
less well-developed wing may be found on a single keel. The 
teeth borne on the margin of the wing vary greatly; from one 
to four teeth are commonly present and these vary from one to 
four cells in length and from one to three cells in width at the 
base; they may therefore be slender cilia, broad triangular lobes, 
or short slightly projecting cells or groups of cells. The beak 
is short and relatively broad, consisting of two or three superim- 
ee ot circles of cells. 
