Notes. 
95 1 
THE EXTENT OF THE ROOT-SYSTEM OF CUCUMIS SATIVUS.— In 
Sachs’s ‘ Lectures on the Physiology of Plants ’ (Eng. ed., p. 13) the following sentence 
occurs : £ S. Clark has taken the trouble to measure the length of all the roots of a large 
gourd plant and found that it amounted to 25 kilom.’ This statement is repeatedly 
quoted in other treatises on Physiology, e. g. ‘ Pfeffer’s Physiology/ Eng. ed., vol. i, 
p. 153, Jost’s ‘ Lectures on Plant Physiology 5 , Eng. ed., p. 28, &c. The reference is 
not given in any of the more recent works nor by Sachs himself. It may be of interest 
to quote the original statement, which occurs in a paper by W. S. Clark, President of 
the State Agricultural College, Amherst, Mass., and published in the 22nd Annual 
Report to the Massachusetts State Board of Agriculture. The paper in question 
deals with a wide range of subjects, and is more in the nature of a popular discourse 
than a scientific research. Some of the statements made by the writer are sufficiently 
startling. For instance, he states that roots of Clover one year old penetrated the soil 
perpendicularly to a depth of 8 feet, Lucerne roots to a depth of over 20 feet, and 
that, on the authority of an unnamed Indian officer, those of Prosopis spicigera reached 
a depth of over 69 feet 1 The last statement, at least, must be accepted with reser- 
vations, more especially when resting on an anonymous statement by one presum- 
ably without special botanical knowledge. Pfeffer (Phys., vol. i, p. 258) quotes 
Clark as his authority for the record that the Birch gives off 6*8 kilos, of sap per day in 
cases of active bleeding. Clark’s statement is, however, that a Paper Birch 15 inches 
in diameter gave off, in less than two months, over 1,486 lb. of sap, a maximum 
of 63 lb. 4 oz. being reached on May 5th. This would give on an average 24-4 lb., 
or approximately n-i kilos, per day over 60 days (nearly twice the amount quoted 
by Pfeffer), while the maximum would represent about 28-5 kilos. 
In ‘ Nature ’ of June 3, 1875, Clark’s paper is reviewed at some length, and the 
reviewer, although he says he has ‘ no reason to doubt the accuracy of the statements 
contained in Mr. Clark’s paper ’, expresses a desire ‘ to see the observations repeated ’ 
— a scepticism justifiable in view of the remarkable observations recorded by Clark. 
One of these deals with the length of the entire root-system of a ‘ squash-vine ’ 
(Cucurbiia maxima), and since Clark’s measurements have been quoted again and 
again without comment, and as the original paper is not very accessible, it may be 
worth while to give the quotation in full : 
‘ But our squash-vine affords the most astonishing demonstration of all that has 
been said about root-development. Growing under the most favourable circumstances, 
the roots attained a number and an aggregate length almost incredible. The primary 
root from the seed, after penetrating the earth about four inches, terminated abruptly 
and threw out adventitious branches in all directions. In order to obtain an accurate 
knowledge of their development, the entire bed occupied by them was saturated with 
water, and, after fifteen hours, numerous holes were bored through the plank-bottom, 
and the earth thus washed away. After many hours of most patient labour, the 
entire system of roots was cleaned and spread out upon the floor of a large room, 
where they were carefully measured. The main branches extended from twelve to 
fifteen feet, and their total length, including branches, was more than two thousand 
feet. At every node, or joint, of the vine was also produced a root. One of these 
nodal roots was washed out and found to be four feet long, and to have four hundred 
and eighty branches, averaging, with their branchlets, a length of thirty inches, making 
