ON THE FORMS OF POLLEN-GRAINS. 281 
Adopting my theory of rosaceous andrccia, there is no confluence of the 
lobes of the compound stamens in JVatíallia, i.e. there are no inter- 
staminal lobes 
In iesinus, I must express my obligations to Mr. M‘Nab, for his 
having kindly permitted me to make what use I required of the collec- 
tion of Potentillas in the Botanic Garden, from which I obtained the 
greater number of the species which I examined. 
EXPLANATION OF PrarE LII. 
by analogy) being indie yt pe ot huc D^ P larger representing 
the older, the smaller the yo unger iagram representing 
ie staminal ar rrangem ment in species of Potentilla Salling — typeI. This 
figure rom my paper o e androcium o: ntzelia, eer The 
antipetalous stamens are represen ota as the most internal Pat th in many Po- 
tentillas (in the adult state, at least) they appear to be ex ternal to t the antise- 
patous stamens, 2. Diagram of arrangement in les of Potentilla fallin ng 
lagra epee} 
under type 3. 2 of arrangement in species of Potentilla od 
tidie er DI . Dia 
tions of Lg Y ede of Potentilla fruticosa ; 4:80, parts ep icalyx ; $5 d 
p. i so-called. Between the petals festoons of si mill: extend. 
Of the two festoons represented, one contains five, ie pem Tour stamens 
ON THE POLLEN-GRAINS OF CERTAIN RANUNCULEZE 
AND OF LOTUS CORNICULATUS AND AJOR. 
By GEORGE GULLIVER, EsQ., F.R.S. 
Though the importance of the forms and structure of the elementary 
parts of plants has long been recognized in the grouping of the great 
divisions of Pinsao but very little aid has yet been derived 
from histology or microscopic research in the discrimination of near 
allies of this class. And no wonder, after Schleiden had concluded 
that a further advancement of systematic botany could i be ex- 
pected from mere anatomy and physiology; and when, indeed, we see - 
how much the cells and other parts of the intimate structure of the 
members of the same and connatural orders are alike, while the differ- 
ences are comparatively few and not discoverable without many exact 
comparative examinations. Still after such observations have been 
sufficiently extended, we shall surely acquire a valuable addition to our 
