426 Prof. Linney on the Anatomy of the Roots of Ophrydeæ. 
The roots of all the other Ophrydeæ, whether European or not, which I 
have had the opportunity of examining, are constructed essentially in the same 
manner as that of Satyrium pallidum. The differences I find among them 
consist chiefly in the size and shape of the nodules, and in the proportion they 
bear to the surrounding parenchyma; in the quantity of starch formed in the 
latter; and in the way in which sections of the tubercles are affected by expo- 
sure to the air. In Orchis maculata, for instance, there is more starch than 
usual, the nodules when fresh are not much larger than the cells of BATT OUR: 
ing parenchyma, and the section of the root remains white, while * Sauce 
pallidum it becomes deep brown. Beyond this I have observed nothing which 
deserves notice. 
But while the presence of nodules is so universal in this tribe of Onchig 
daceæ, it is not a little singular that they should be as generally absent in 
the tubercles of the other tribes of the same natural order. Up to the present 
time I have not succeeded in detecting them in any species of Neottiee os 
Arethuseæ, of which I possess roots. In the tubercles of New Holland Orchi- 
daceæ the cells appear to be exclusively occupied by starch, with which they 
are in fact filled; at least, such is the case in Glossodia minor, Thelymitra 
carnea, and another species, Caladenia testacea 
many species of Diuris and Pterostylis. 
I have already stated that the nodu 
slowness with which their horny cont 
» Corysanthes bicalcarata, and 
les appear to be homogeneous. But the 
ents are acted upon by the alcoholic so- 
lution of iodine, and the frequent arrangement of the secretions of plants in a 
stratified manner in the lignified parts of vegetation, led me to suspect that 
this homogeneity was only apparent. Nevertheless, for a long time I sought 
in vain for evidence of their contents being organized; in whatever way they 
were cut, whatever reagents were employed, sections of the nodules presented 
the same unvarying uniform surface. At last, upon examining some Covent 
Garden Salep,—a coarse preparation of wild Ophrydec, thin slices of which 
I had made with a knife whose edge had lost its keenness, and which therefore 
bruised the Salep while cutting it, an indistinct granular appearance became 
visible upon some of the divided nodules, not however so well defined as to 
_ enable me to judge of its real nature. But upon charring the slices by 
Mr. Reades process, a beautiful definition of the granulation was obtained. 
