Dr. T. Bell Salter on some forms of Rubus. 363 
anteriorly to the appearance of shoots of the final form, are yet 
some which even flower and mature their fruit, and it is these 
which may be most apt to mislead. There is reason too to believe 
that in some instances, the plants, from local causes, become ar- 
rested permanently at this stage of their development. [ shall 
have an instance of this nature to record in one of the forms I 
propose describing in this paper. 
On the subject of the growth and development of Rudi I hope 
ere long to have more certain information, as through the kind- 
ness of Mr. Lawrence of St. John’s, Isle of Wight, I already have 
numerous species under cultivation, many of which are raised 
from seed. By this means also I have the advantage of perceiving 
the effect of situation on these plants. Already some, which 
coming from different situations were in some degree varieties, 
have acquired the same form. 
' For observations on the effects of soil and situation, I may 
refer to some remarks of my own which have appeared in the 
‘Phytologist’?*. Observation in St. John’s Garden has already 
proved the identity of R. leucostachys (Sm.) and R. vestitus 
(W. and N.), since these extremes planted together last year are 
this year nearly identical. 
To the remarks on the effects of soil and situation I may now 
add, that I have since observed that these plants are also much 
modified by season. 
All the preceding remarks tend rather to point out the diffi- 
culties to be met with in distinguishing the species of this group, 
than to offer any method by which to meet them. As regards 
any general rule for distinguishing species, applicable to the whole 
group, or even to the single sections of it, I regret to say that I 
have none to offer. An habitual observation of them accus- 
toms the eye to recognise the various forms, and I am sanguine 
that it has also enabled me, to some extent, correctly to unite 
many of these as single species ; but as regards the artificial cha- 
racters by which to define them, and especially such as shall 
render them easy to be recognised by others, it must be ad- 
mitted that in this there is much difficulty. It is on this ac- 
count that good figures are so truly valuable for illustrating Rudi, 
a fact which has rendered the elaborate and well-executed ‘ Rubi 
Germanici ’ of Weihe and Nees of such essential service. 
The clothing of the barren shoot and every character pre- 
sented by the calyx appear to be hitherto those mostly depended 
on. Most of the other parts afford some characters of more or 
less value ; doubtless however some might be very much more 
employed than they have been, such as the form of the petal and 
* Vol. ii. pp. 105, 106. 
2D2 
