On the finding of Carduus tuberosus at Avebury. 209 
ficant note, “Many hybrids occur in this genus.””—Manual of British 
Botany, 4th edition. And my friend Lees has kindly furnished me 
with the following note upon another disputed species which 
directly bears upon this question. 
“In August 1856, I found the “Cardwus Fosteri,’ (Smith) ina 
field near Crowle, Woreestershire. In the same marshy field was 
a considerable quantity of Carduus pratensis (Huds.), and a very 
numerous growth of “C. palustris” (Linn.) so as to give rise to an 
immediate suspicion of its hybridity, and upon examination the 
characters shown by “‘C. Fosteri”’ (Smith), were exactly intermediate 
also. The leaves were much like those of “C. palustris” (Linn.), 
while the stem and flowers were in small clusters, instead of being 
single as in the latter. Indeed the result of my examination con- 
vinced me that C. Posteri (Smith) could be only a hybrid, and this 
I stated in an account I sent to the “ Phytologist,” and which ap- 
peared in the September number of that Journal for 1856.” 
For the present then I must content myself with having offered 
presumptive evidence of the non-specific character of what is after 
all a decidedly distinctive form, and as I have brought home some 
specimens and planted them in my botanical garden, where I shall 
also introduce the “C. avaulis” (Linn.) and “‘C. acanthoides (Linn.), 
I shall look forward to the result of experiments with these with 
no little degree of interest, as in all probability like so many other 
experiments which I have been enabled to perform in the same 
direction, these may serve still more to perplex the question of, 
What is a species ? 
Cirencester, January, 1858. 
