FOLIAR ORGANS. ove 
tubular, horn-like projections, and in the centre a 
thread-like process representing the midrib and termi- 

Fie. 185.—Supernumerary leaf of hazel. 
nated by a small two-lipped limb.’ Dr. Ferdinand 
Miiller speaks of a leaf of Pomadervris elliptica as bearing 
a secondary leaf on its under surface.’ 
The leaves of Heterocentron macrodon have likewise 
been observed occasionally to produce leaflets from 
their upper surface. 
To this production of leaves from leaves the late 
Professor Morren applied the term ‘ autophyllogeny.’” 
The Belgian botanist figures a small perfect leaf sprie- 
ing from the nerves of the upper surface of the primary 
leaf in a species of Miconia. As in the hazel, the direc- 
tion of the adventitious leaf is inversely that of the 
primary one, the upper surface of the supernumerary 
leaflet being turned towards the corresponding surface 
of the normal leaf. A similar occurrence took place 
in Gesnera zebrina, but the new growth in this case 
sprang from the lower face of the leaf. Morren 
explains the appearances in question by. supposing 
that the supplementary leaf is one of a pair belonging 
to a bud borne on a slender stalk. This stalk and one 
of the bud-leaves are supposed to be inseparably united 
' «Bull. Soc. Bot. Fr.,’ vol. vii, 1860, p. 587. 
> «Fragment. Phyt. Austral.,’ part xx, p. 270. 
* «Bull. Acad. Belg.,’ xvi, pt. i, p. 60, “ Fuchsia,” p. 125, ¢. ic. 
