330 BOTANICAL GAZETTE [NOVEMBER 
In this region the pith is large, composed of slender interlacing 
hyphe, the majority of which seem to run transversely. Mingled 
with the ordinary hyphe of the pith web are numerous trumpet 
hyphe with the well-known sieve-plates, where the flared-out ends 
of the cells come in contact with each other. Very many ot 
the trumpet hyphz run transversely in the pith web, and they 
are perhaps rather less abundant in the perimedullary portion 
where they take principally a longitudinal direction. The inter- 
stices between the hypheare filled with gelatin, and immediately 
outside of the general mass of interlocking and interlacing fila- 
ments is a sheath of sclerenchyma, between the longitudinally 
extended cells of which occasional pith hyphe extend trails 
versely. The pith in this region occupies about one third of the 
diameter of the cross section. The remaining area is composed 
of three well-marked layers. Immediately outside of the pith 
is the narrow band of sclerenchyma just described, an area om 
staining deeply with aniline-water-safranin. Outside a this 
sclerenchyma lies a band of fundamental tissue having the 
appearance of parenchyma in cross section. The content 
cells are not strongly granular. Outside of the last mention 
region is chlorenchymatous tissue, in which the cells eg! 
marked tendency to develop with their long axes perpendi : se 
to the epidermis. Surrounding the whole is @ eee 
epidermal layer of low prismatic cells. The longitudinal se" 
through this area does not show a development of the of : 
cells so abundant in older stipe and characteristic of gee 
of secondary thickening, but the layer directly under the ¢ | 
chyma is composed of almost isodiametrical cel!s " om the 
ing in form to elongated-prosenchymatous in passing ond Oe 
periphery towards the pith. The cells immediately ne 
pith are very long, some of them measuring 1™° fon es not 
while the lumen as revealed in cross sections is sone 
over 24 in diameter. This condition reminds one 5 ee = 
shaped sieve-tubes of Nereocystis, which occur in the Bos callus 
ing region of young stipe and lamina, but no end see in othe 
has been detected in these cells of Lessonia, whic = 
Is rapidly chang” 
