ON A NEW SPECIES OF HELIANTHEMUM. 617 
V/4 378 Stereocaulon paschale, Ach. 
" « 379 Parmelia leucomelas, 'Tayl. 
vv 380 Cenomyce gracilis, Ach. 
~ “381 Usnea plicata, Ach. 
P” ago Cenomyce rangiferina, Ach. 
v “383 Ramalina fraxinea, Ach. 
Ye 384 Roccella tinctoria, DC. 
Description of a new British Species of HELIANTHEMUM ; by 
J. E. Puancuon, Docteur en Sciences de Montpellier. 
(Tas. XXI.) 
Tue few annual species of Helianthemum which rank with 
H. guttatum in the section * Tuberaria,” are remarkable for the 
deficiency of stipules to their lower leaves only, and for the 
absence of bracteas at the base of their pedicels. H. gut- 
tatum, especially, though a variable plant as regards size 
and pubescence, preserves in all stages its pedicels destitute 
of bracteas and diverging at right angles, even when the 
fruit is mature. The growing plant, with which I have been 
long familiar in the South of France, is thus characterized, 
and the same peculiarities exist in all the specimens I have 
€Xamined from Spain, Italy and Central France. Being 
Perfectly acquainted with the aspect of this pretty species, 
I could not recognize it in specimens, bearing the name of 
Helianthemum guttatum, which are preserved in the rich 
barium of Sir W. Hooker, to whom they were given by 
Mr. Wilson of Warrington, who had gathered them him- 
Self on the mountain of Holyhead, in the Isle of Anglesey. 
The straggling mode of growth, with short, numerous and 
: Otomous bunches of flowers, the existence of bracteas 
t fYen to the upper flowers, and of pedicels, which at first. 
r tly bend down, but rise up when the fruit is ripe and stand 
P. at an angle of forty-five degrees to the axis of the cluster, 
= Such were the characters, which at a first glance, suggested 
the idea that the plant was specifically distinct from H. gut- 
—... VOL. 111, 27 
