292 DR. M. T. MASTERS ON SOME POINTS ІМ 
ух жегом.— P yllody, or leafy condition of the pistil, is of not infrequent occurrence 
in the Primrose. Imperfect development is also not uncommon, in which case an 
imperfect tube or sheath, open at the top without trace of style, surrounds the placenta, 
the latter being in such cases usually elevated on a long stalk (Pl. XL. fig. 4). "This is 
in accordance with the natural development of the carpel, save that it is arrested. In 
other cases, especially in the Chinese Primrose (P. prenitens), the carpels assume а 
petaloid guise, the entire pistil being completely open at the summit (Pl. XL. figs. 8 & 9). 
Dialysis, or a lack of union of the carpels, is of frequent occurrence in the Primrose, 
there being in the simplest cases five open carpels, each with its separate style and 
stigma. Ina double Polyanthus lately shown at the Royal Horticultural Society, the 
calyx was normal, the corolla in two rows, the first row normal, with stamens as usual. 
Within them was a second corolla, also provided with stamens. Тһе gynscium con- 
sisted of five more or less detached petaloid open carpels, each with a long style and 
stigma. One of these carpels was remarkable for having its margins divided into lobes; 
of these lobes the uppermost were prolonged into styles (Pl. ХТ, fig. 11), the lower bore 
imperfect ovules; so that the same сатреПагу leaf bore secondary carpels and ovules, 
exactly as in the case of the pistillodie stamens previously mentioned (Pl. XL. fig. 1). 
PLACENTATION.—The free central placenta of Primulacez has naturally attracted much | 
attention on the part of morphologists, some of whom have considered it to be of axial, 
some of foliar nature. The former view is that which is most generally adopted, though 
of late it has been contested by men of authority, on which account it may be well 
briefly to allude to the most important papers that have been published on the subject. 
A. de Saint-Hilaire * describes the placentas as originally connected with the interior of 
the style by a little thread, which is afterwards obliterated. Duchartre, in the paper 
before referred to, combats this view, and says that in the development of the ovary and 
the placenta “ Гоп remarque deux développements marchant parallélement et simul- 
tanément; celui de la portion appendiculaire ou des parois de l'ovaire, du style et du 
stigmate, et celui de la portion centrale ou axile. Celle-ci pendant toute la durée de son 
développement reste libre et indépendante de la partie externe du verticille femelle; 
elle joue absolument le róle d'un petit rameau végétant sous un abri protecteur, le seul 
rôle du reste qu'elle puisse jouer. D'abord entièrement homogène elle se laisse diviser 
plus tard en deux parties, l'une inférieure, qui donne naissance aux ovules et qui possede 
toute la structure de l'axe lui-méme, l'autre supérieure et stérile uniquement celluleuse, 
dont le développement est, le plus souvent, trés-horné, qui parfois s’accroit . . . et devient 
un petit cône logi dans la partie inférieure du canal stylaire."' 
Payert entirely adopts the conclusions of Duchartre, as, "m do most modern 
observers. 
_ А large number of teratological phenomena might be cited in favour of this view, such 
as the instance cited by Duchartre in which a flower-bud was observed at the apex of 
the placenta i in Cortusa Mathioli. Other prolifications of a similar character have been 
p _ Mémoire sur les plantes auxquelles on attribue un placenta central libre (1816). 
à Е inogé nie Végétale, p. 611. 
