400 W. Lauder Lindsay’s Experiments on the 
TABLE XXIII. 
In the following species, which are said to be used in various 
countries for dyeing brown, the colouring matter also exists 
ready formed in, and gives the predominant tint to, the thallus 
of the plant. 
Cetraria islandica. Parmelia physodes. 
Gyrophora cylindrica. Sticta pulmonaria. 
Parmelia omphalodes, . scrobiculata, 
TABLE XXIV. 
The following lichen-genera, on account of the exceedingly minute 
size and delicate consistence of their thallt, from the position, 
nature, and colour of their apotnecia, &c., have beenentirely 
excluded from my experiments, and are not at all likely ever to 
furnish species useful as dye agents. 
Calicium. Glyphis. Opegrapha. 
Arthonia. Graphis. Verrucaria. 
Biatora. Pyrenula. Thelotrema. 
Chiodecton. Pyenothelia. 
For similar reasons, only a few species of the following genera 
were subjected to experiment ; the results yielded are equally 
unfavourable, 
Beomyces. Lepraria. Psora. 
Endocarpon. Spiloma. Squamaria, 
Pertusaria, Variolaria. Placodium. 
Most of the angiocarpous lichens have thus been excluded from 
the experiment, and promise to be utterly valueless as dye agents ; 
and inter alia, 
Chiodecton. Pertusaria. Sphzerophoron. 
Cliostomum. Pyrenothea, Strigula, 
Endocarpon. Sagedia. Thelotrema. 
Gyalecta. Segestrella, Verrucaria, 
