5^4 



PHANEROGAMS. 



considerably elevated even before the formation of the carpels ; the carpels are then 

 seen in a whorl, and are attached by means of their coherent margins to the elevated 

 axis ; each forms what may be described as a pocket attached to the axis. As the 

 axis becomes elongated, the margins of the carpels form radial dissepiments sepa- 

 rating the pockets, which widen into loculi ; and the carpels finally rise above the 

 apex of the axis. In Cerasiiwn and other genera the dissepiments also rise above 

 it as free lamellae which do not meet in the centre, so that the ovary is quinque- 

 locular below, while in the upper part it remains unilocular. The ovules are 

 produced in two parallel rows on the axial face of each loculus, this face being 

 apparently formed from the axis itself. In some genera of Caryophyllese it seems 

 probable that the placentae are axial, while in others they would appear rather to be 

 carpellary. 



1[ M 



Fig. 390.— /—^V/ stages of development of the ovary oi Phlomis ptcngens (a Labiate), ^in longitudinal, the rest in trans- 

 verse section; A a gynaeceum seen from without ready for fertilisation; B the same in longitudinal section, the lines u u, 

 o (? correspond to the transverse sections VI and VII; pi the placenta, x the spurious dissepiment, /"loculi, sk ovules, c wall 

 of the carpel, t disc, g style, n stigma. 



Among Superior Ovaries with axial Flacentation, those of Typha, Naias, and 

 Piperaceae^ require especial mention. In these cases the very simple female flower 

 consists (with the exception of the perianth of Typha, which is represented by hairs) of 

 nothing but a small lateral shoot transformed into an ovary with a central ovule ^. 

 The apex of the axis of this shoot itself developes into the terminal nucellus of the 

 ovule, round which an annular zone grows up from below, overarches it, closes up 

 above, and thus forms the wall of the ovary. In Typha only one style and stigma 



^ Magnus, Zur Morphologic der Gattung iVnms (Bot. Zeit. 1869, p. 772), — Rohrbach, Ueber 

 Typha (in Sitzungsber. der Gesells. naturf. Freunde Berlin, Nov, 16, 1869). — Hanstein u, Schmitz, 

 Ueber Entwickelung der Piperaceenbliithen (Bot. Zeit, 1870, p, 38), 



^ As in the case of the 'axial anthers,' so here also some uncertainty still exists. In a letter 

 to me Schenk distinctly denies the axial nature of the ovule in Typha; he states that it is lateral, 

 that it appears as a small protuberance on the wall of tlie ovary, a position which it retains until 

 maturity. 



