180 Mr. Woops on the British Species of Rosa. 
s. Peduncle setose; fruit somewhat ampulliform, dark. Found 
by Mr. Robertson near Newcastle. I have never seen any 
specimen: it may perhaps be a dark-fruited variety of 
R. rubella. | 
R. spinosissima may be easily distige from R. involuta by its 
simple serratures. The only other British plant with which it could 
be confounded is R. rubella; but in R. spinosissima the aculei are 
numerous, strong, and expanded at the base, and gradually di- 
minish into sete, those of an intermediate size being as nume- 
rous as those wbich are larger or smaller. In R. rubella the 
prickles are few, very slender, little expanded at the base, and 
nearly of a size; while the setze are much more numerous and 
crowded than in R. spinosissima : the sete of the peduncle e also. 
in R. rubella are long and ‘slender; whereas the peduncle of. 
R. spinosissima is biher naked as in z, or with the glands on short 
peduncles as in B, or with arms, which are rather aculei than setze, 
as in y. But perhaps the existence of such variations in this 
species ought to induce us to place but little dependence on this 
character. Both the colour and shape of the fruit of R. spinosis- 
sima vary considerably ; but it is probably never either so red or 
so long as in R. rubella. | 
R. myriacantha, Lam. et Dec. F "j. Res iv. A59, &.vi..583, ap- 
pears to be allied to R. spinosissima ; but the footstalk and the - 
under surface of the leaves are covered with glands. Lamarck 
and Decandolle also mention that there is a difference in the ser- 
ratures of the leaves and in the leaves of the calyx, but they do 
not point out in what it consists. Desv aux, Journal de Botan. ii. 
118, says the serratures of R. myriacantha are compound; but in 
a specimen of this species from Decandolle, in the Herbarium of 
Mr. D. Turner, they are simple. 
I am by no means confident that the figure in the Fl. Danica, 
t. 398, is intended for this plant: it differs in the aculei, which 
are 
