INTRODUCTION 
3 
In 1671 he discovered that from some a permanent dye of a 
carnation-red colour could be obtained by mixing them with 
ley of ashes. 
The physician Marcello Malpighi (1628-1694) was the 
earliest systematic writer on galls. He published in 1686 
a treatise, “ De Gallis,” concerning the galls of Italy and 
Sicily. His disciple was Dr. Derham, Canon of Windsor, 
who comments upon Malpighi’s observations and his own 
in the notes to his Boyle Lectures (1711-12), in which he 
writes: “ I find Italy and Sicily more luxuriant in such 
productions than England, at least than the parts about 
Upminster (where I live) are. For many, if not most, of 
the galls about us are taken notice of by him [Malpighi], 
and several others besides that I have never met with, 
although I have for many years as critically observed all 
the excrescences and other morbid tumours of vegetables 
as is almost possible, and do believe that few of them have 
escaped me.” Derham was fully aware that galls may 
contain parasites, and quaintly remarks: “ I apprehend we 
see many vermicules, towards the outside of many oak- 
apples, which I guess were not what the primitive insects 
laid up in the germ from which the oak-apple had its rise, 
but from some supervenient additional insects, laid in after 
the apple was grown, and whilst it was tender and soft.” 
That much attention was given to the subject by investi¬ 
gators in the latter part of the eighteenth century and early 
in the nineteenth is evident from a perusal of the article on 
“Galls” in the fifteenth volume of Rees’s “Cyclopaedia,” 
published in 1819. The author observes that galls are 
morbid excrescences originating from those parts of a plant 
that are in most vigorous growth, in consequence of the 
attacks of insects; that the two varieties of British Oak 
bear several kinds of galls ; and that the main stems of the 
large shrubby kinds of Hawkweed (Hieracium sabaudum 
and H* umbellatum) are often attacked and swell into oval 
knots, in which, while growing, young insects may be found 
latent. 
