PROF. OLIVER OX THE STRUCTURE OF THE ANTHER. 
5 
margin, upon each side of the med 
wn 
hetween the stamens and petals, in Atragene alpina (taf. xiii. 31(> B 
stages intermediate 
i T i 
tcli of 
the two lohes of thickened parenchyma a longitudinal suture is found, which answers to 
their line of dehiscence. That this line does not correspond to the leaf-margin he further 
endeavours to show from a monstrous flower of Colchicm (p. 33G, taf. xiii. 319). Tiwi- 
ranus* considers Bischoffs modification required to suit Cassini's theory to nature. 
He 
concludes his observations on anther-morphology, however, thus : — " Dass jedoch dieses 
nicht als allgemeines Bildungsgesetz aufgestellt werden konne, zeii^t z. B. Paris, wo au- 
genscheinlich der Pollensack durch den Rand des zu einem Tracer verschm alert en Bin- 
menblattes, und die beiden Klappen von den bciden Oberiliichcn desselben gebildet werden.'' 
With regard to Paris, vide infra, p. 127. II. v. Mold's paper, referred to above, contains 
an excellent exposition of the state of the question of ant lief morphology. The cases 
which he 
pecially refers to of metamorphosis of 
into carpels — the anther- 
sutures becoming ovuliferous — do not, as he himself observes, aiford conclusive evidence 
in favour either of the theory of Cassini or that of BischolF. Tin 4 e i reu instances alluded 
to by Roeper, of the red colour of the leai'-margin of certain EuphorbiaceeB being f and 
again in the anther-suture, and the presence of cilia on edges of leaves and on the lines 
of suture in the anther, Von Mohl admits to be very important, if not 
that the latter 
to the leaf-margins in some 
hilt-, on tin 4 other 
d 
transitional forms presented by the Rose, as cited by BischofF, by the Poppy* and Nigel I 
clam 
incontestably show that the anther-cells in these plants do not originate 
opposite to each other in the leaf-parenchyma on each side of the midrib of the leaf, b 
distinct points 
face of the lamina — the anterior ( Us 
to the median 
line, the posterior to the margin. In N. domascena, described by Von Mold 
rior cells are parallel to the midvein 
lower extremities cont 
the posterior and marginal cells having their 
? 
to them 
hile 
upper 
ends are remote. II. von 
of anther 
in thi 
Mohl does not commit himself exclusively to either view 
essay. 
Mr. Bentham has kindly called my attention to the observations upon the homology of 
the anther-cells contained in a review of Dr. A. Gray's " Genera of the Plants of the 1'nited 
States" f. The reviewer considers that the anthers are homologous with the 'glands' which 
frequently occur at the top of the petiole, or near the base of the limb, in several genera 
of Dicotyledons, remote in the order of 
natural affinity 
He savs, " In the 
forming the andrcecium a partial return to the sy 
much as the filament is entirely reduced to the -v 
of stem-leaves takes place, inas- 
system, its glands are converted 
into anthers, and the cellular parenchyma is only occasionally represented in an expanded 
connectivum, or slight membranous expansion of the filament." I have not made the 
minute structure of these curious appendages my study ; I have merely inspected them 
with a lens in Elceococca, Ale u rites, and allied genera of Euphorbiaceae, and in P 
bium. I must acknowledge, however, that I am unable to view the question of their 
homology in the same light with the reviewer, whose theory appears to rest upon a 
curious analogy in respect chiefly to the position of these glands and anther-lobes, rela- 
* 
Phys. d. Gewachse, i. p. 277. 
f Kew Misc. vol. i. (1849), p. 3.~. 9 
3m2 
