250 BOTANICAL GAZETTE. [ October, 
haustive study even of the few species examined, but rather 
as an introduction to an intended wider and more detailed 
investigation. ere 
n the whole range of vegetable anatomy there is, per- 
haps, no other subject about which so much has been written, 
which still remains so obscurely treated in the ordinary text- 
book as that of cork formation in general, and more especially 
of that peculiar process which leads to the formation of bark. 
One reason for this is, without doubt, the lack of agreement 
among different authors in the use of the terms referring to 
the outer growths of woody stems of dicotyledons and gym- 
nosperms. For example, several text-books, written in Eng- 
lish, differ in the definition of the term bark, which, though 
acknowledved to be a general, rather than scientific term, 
still deserves to be used in a manner to make clear what part 
of the stem is meant. Another very probable reason is, the 
difficulty of the subject itself and the fact that each successive 
a description of cork in an article entitled, Untersuchunge? 
tiber die Entwickelung des Korkes, etc.2._ In this he showed 
that the bark owes its origin to the development of cork- 
lamellz inside the rind.? Rudolf Miiller4 followed him, but bee 
work was limited to the relation of the cork to the other tissues 
of the rind of deciduous trees. Later, Hanstein,°® Schacht 
and Schleiden? made various studies in this field. After 
2Verm. Schriften, p. 212. 
ere 
* Rind here in the general sense of German “Rinde,” i. ¢., all that part of the S*™" 
outsile the cambium rin ary rind, those cells of the fundamental tissue of me: 
stem between the epidermis and the ring of vascular bundles. Secondary rind, all 
a , 
phloem tissue, both of the original vascular bundles and whatever secondary growth 
may be added from the cambium layer. 
‘Breslau Dissertation. 
0 Salata ag liber den Bau und die Entwickelung der Baumrinde. 
*Grundziige der Wissenschaftl, Botanik. 3d edition. Page 283. 
pees a Sip. 
