of Lathrea Squamaria, $c. All 
parasitic on roots, it is copiously supplied with £rue leaves, while 
it shares, in common with them, the appearance indicative of the 
want of those organs. Assuming for the present that the tooth- 
like scales of the subterraneous stem are really leaves, the appa- 
rent anomaly will be reconciled by reflecting that their functions 
. are necessarily performed in the total absence of light, that 
essential agent in the production of the common livery of the 
vegetable kingdom. Neither is their cuticle perforated by any 
pores. In order to ascertain if light would produce any change, 
on the 20th of November last I carefully laid them bare and 
washed away the soil; but after having been as much exposed 
as their gloomy situation would admit till the middle of January, 
they had not acquired the slightest approach to a green colour, 
nor any absorbing pores. Frost now set in; and on again 
examining them on the 5th of February, I found the uncovered 
parts blackened and destroyed by this unnatural exposure. A 
head of flowers has since shot up within two inches of the spot, 
without any change in its natural appearance. i 
"The general shape and character of the leaves, though they vary 
considerably in detail, are known to most botanists, and may be 
understood by reference to Tan. XXII. Fig. 2. & 3, and Tan. 
XXIII. Fig. 6. 7. & 8. If their outer or convex surface be viewed 
attentively by the naked eye, especially those on the newly formed 
branches, a number of longitudinal parallel strize, or tubes, may 
be observed under the cuticle, whiter and more diaphanous than 
the contiguous parts, but having no apparent orifice or external 
communication. On dissecting the leaf, these are found to be so 
many hollow cells or chambers imbedded within its solid succu- 
lent substance; and varying in number from six to twelve accord- 
ing to the size of the leaf. A lens of moderate power shows their 
interior surface to consist of a variety of irregular corrugations 
or tortuous ridges, which increase the superficial area very con- 
siderably. 
