70 REVIEWS. 
following. species, viz. Roccella, Lecanora, Umbilicaria, Gyro- 
phora, Urceolaria, Parmelia, Evernia, Borrera, Ramalina, Leci- 
dea, Isidium, Spherophoron, yield fine red colours, and Parmelia, 
Sticta, Cetraria, Nephroma, Solorina, Scyphophorus, Stereocau- 
lon, Borrera, Lecidea, Peltidea, Collema furnish good brown 
colours. The Doctor further states that— 
XIX. Of 540 specimens examined, 
22 gave rich purple or red colours to ammonia alone (¢. e. simple ma- 
ceration). 
8 gave rich brown colours to ammonia alone. 
81 alcoholic solutions gave rich purples or red on the addition of am- 
monia. 
127 alcoholic solutions gave well-marked orange on the addition of 
ammonia. 
42 alcoholic solutions gave well-marked greenish-yellow on the addi- » 
tion of ammonia. 
79 alcoholic solutions struck a deep blood-red with solution of chloride 
of lime. 
XX. The whole subject of the intimate chemistry of the Lichen colour- 
ing matters is in a very unsatisfactory condition, demanding reimvestiga- 
tion; and I therefore repeat, that the branch of the Natural History of the 
Lichens, to which in this and previous papers I have endeavoured to draw 
scientific attention, will form a subject of research to the botanist and 
chemist, and possibly a remunerative one to the manufacturer. 
At the end of this introductory matter, for the six pages of 
text are only a statement of facts and results deduced from the 
tables which constitute the remainder of the tract, it is said, “ I 
subjoim some simple methods of detecting the various Lichens.” 
We have not seen these methods. If we had, we should have 
printed them pro bono publico. We have looked for them, but 
with the exception of chemical properties, characters of no use 
to mere botanists, we have not been able to detect in the work 
sent to us any means by which one Lichen is to be distinguished 
from another. If Dr. Lindsay will send them to us, we will give 
them publicity. We reiterate our thanks to the author of this 
pamphlet, and shall be very well pleased to have the honour of 
enrolling his name among the other honoured and stated contri- 
butors to our pages. 
