Present State of the Genus Cinchona. 39 
products obtained by Dr. De Vrij and Mr. Howard from 
the cznchona succirubra grown by M‘Ivor, are the measure 
of the superiority of this species over the calisaya. In the 
writer's opinion, the reverse is the truth,.and though, from 
some cause, equal success has not been attained with the 
latter in the East Indies, he does not at all despair of seeing 
the calisaya reassume there its rightful supremacy as the 
queen of all quinine-growing species. 
He is the more confirmed in this hope, because the 
calisaya, though found so delicate in India, is growing 
luxuriantly under double glass in Mr. Howard’s stoves— 
one raised from seed sent by Sir R. Murchison to Kew in 
May, 1864,* two or three inches in height when first planted 
out in October, 1864,—having, in lttle more than two 
years, attained an elevation of more than seven feet, and 
spreading in every direction. 
Mr. Markham sayst “The C. calzsaya, the most famous 
of all the South American bark trees, and which, in its 
native forests, is alike the most beautiful and the richest in 
quinine, has not been a success in India. I was grieved 
to see the plants of this species only five feet ten inches 
high, and six and a half inches in girth, at an age of three 
years, wnile their stunted and shrubby appearance, with 
dim coloured leaves, is as different as possible from the 
glorious calisaya of the Caravayan forests.” 
Mr. Howard is endeavouring, in COLDSE RC USS with 
Mr. M‘Ivor, to ascertain the occasiofi of this contrast. It 
is not impossible that something may be due to the differ- 
ent effect of light passing twice through glass, by which 
means, a large portion of the actinic power (about half, as 
ascertained by photographic effects) isarrested. Mr. Mark- 
ham says,{ that in a position which he examined “ exposed 
to the full glare of the sun, there was a_ profusion of 
Melastomacee and no Cinchone,’ for “the latter evidently 
dislike very exposed situations ;” and again he says, “the 
* Dr. Hooker obligingly traced out the history of this plant by 
application to Sir R. Murchison, who says, ‘“‘’The cinchona seeds 
I sent you in 1864 were brought home by Mr. David Forbes, a 
great explorer of the Peruvian and Chilian Andes. I know that 
he attached some value to these seeds, which he told me 
were from trees of the very first quality in their bark and fructifi- 
cation.” 
+ In letter to the Under-Secretary, &c., 16th January, 1866. 
t Letter to the Under-Secretary of India, June gth, 1860. 
