Ca 
EXPERIMENTS IN THE GROWTH OF PLANTS. 2)1 
a large per centage of Poterium will be present. Three plots are now occupied 
with Poterium, the seed in all cases being labeled Sanguisorba officinalis, a 
circumstance showing either a great want of knowledge or a wilful substitu- 
tion of the one for the other on account of a similarity of aspect and English 
name. 
5. EscuLent VEGETABLES.—A constant change in vegetable diet has 
always appeared to me to be a matter of such great importance, that I seldom 
miss an opportunity of making myself acquainted with the growth and ca- 
pabilities of any new kind that may be introduced, as well as such as have 
nearly passed away on account of the favouritism shown from time to time 
towards new introductions ; and as examples of what I am doing in that way 
I would notice the following :-— 
Potato Yam (Dioscorea Batatas) ‘ Among new introductions 
| A wild Potato ... A to this country. 
The Yellow Lima Potato . F 
Salsafy. - - + + 2 ee ieee the all-but ex- 
Schorzonera . ploded vegetables. 
Cardoons . 
The potato yam is so much like our Zamus communis, as almost to lead 
to the inference of specific ideutity, judging from the vine and foliage, for I 
have not yet seen it in flower, much less in fruit. Its yearly increase of 
tubers seems to me too small to warrant its displacing the potato, for which 
it was recommended in the height of the disease of the latter plant. My plot 
in the Botanical Garden is not nearly so luxuriant as some specimens in my 
private garden, the latter being so much warmer and the soil considerably 
better. Here my plants of this year are climbing up sticks and are as much 
as 2 yards high; what the tuber will be remains to be seen; however, from 
_my present experience I can only recommend it as an addition to the list of 
our culinary vegetables. 
Last winter I was gratified at receiving a box of potato tubers which had 
been sent me by my friend Jenkin H. Thomas, Lieut. R.N., consisting of 
tubers of a “ wild potato,” and also some of a “ Lima potato.” The former 
appears to be a Solanum ; but if of the species tuberosum, it is very different in 
all particulars from our cultivated form, the tubers of the latter are more like 
small kidney potatoes. But from the leaves and the slight indication of flower, 
Ido not think it can be a Solanum at all; but I am informed that they are 
__ usually suld in Lima, so that I must make further inquiries into their previous 
history. I would now remark that a plot of them in my experimental garden 
_ has got on very badly, not more than five per cent. of the tubers growing, and 
_ that in a feeble state; however, three tubers planted in my private garden, 
_ though they were a long time coming up, are now very large plants, and in 
_ full vigour of growth. 
_ As regards the wild potato, Lieut. Thomas writes as follows :—“I pro- 
_ cured them from the top of a small island called San Lorenzo, opposite the 
- anchorage of Callao and town of Lima, in Peru, and I have not the slightest 
» doubt in my own mind but that they are the original potatoe, as the island 
is uninhabited, and fertile only at the top (an elevation of about 900 feet), 
____where these potatoes grew: there is generally a mist over the top, and I think 
___ the temperature from 68° to 70°. The blossom is the same as our domestic 
__ one, but the leaf is prickly and rough; I cooked several of them when I was 
in Peru, but found them bitter and strong, but expect that cultivation and 
a a couple of years’ trial will totally eradicate that.”—In a letter to the author 
ol this report, Aug. 17, 1857. 
(ill ak eas 
P2 
