I 



LESSON 18.] COMrOlNO TISTILS. 119 



arc joined tit (ho iiase only, or else hclow the middle (as in Fig. 

 254), and in some they are muted quite to (he top. 



tl\'2. Kveu when tiie styles are all consolidati-d into one, the sti?;- 

 mas are often separate, or enough so to show l>y the numher of their 

 lohes how many simple pisdls are comhined (o make tlie compound 

 one. In the common Lily, for instance, the tliree lobes of the stigma, 

 as well as the three grooves down the ovary, plainly (ell us tha( the 

 pistil is made of three combined. But in the Day-Lily the thi-ee 

 lobes of the stigma are barely discernible by the naked eye, and in 

 the Spiderwort (Fig. 2'»7) they are as perfectly united into 

 one as the ovaries and styles are. Here the number of 

 cells in the ovary alone shows that the pistil is compound. 

 These are all eases of 



313. I'oinpoiiiiil Pistils willi Iwo or more frlls. namely, with 



as many cells lus there are simple jjistils, or carpels, that 

 have united to compose the organ. They arc just what 

 would be formed if the simjjle pistils (two, three, or five 

 in a circle, as the case may be), like those of a Pa'ony or 

 Stonecrop, all pressed together in the centre of the flower, / 

 were to cohere by their contiguous parts. 



314. As each simple ovary has its placenta, or seed- ^^^ 

 bearing line (308), at the inner angle, so the resuhing ^"^^^ji^ 

 compound ovary has as many axile placentce (that is, as ^^ 

 many placenta? in the axis or centre) as there are pistil-leaves in 

 its composition, but all more or less consolidated in<o one. This is 

 shown in the cross-sections, Fig. 254-256, &c. 



315. The partitions (or Dissepiments, as they are technieall}' 

 named) of a compound ovary are accordingly part of the walls or 

 the sides of the carpels which compose it. Of course they are double, 

 one layer belonging to each carpel ; and in rip(! pods tliey often split 

 into the two layers. 



31G. "We have d(>scri])ed only one, though the commonest, kind of 

 compound pistil. There an; besides 



317. OllC-CclIcd Compound Pistils. These are of two sorts, those with 

 axile, and thos(! witii jxtriitnl placenttc. That is, first, where the 

 ovules or seeds are borne in the axis or centn; of the ovary, ;ind, 

 secondly, where they arc borne on its walls. Tlie first of these 

 Ciises, or that 



Flo. 367. I'i^lil of S|iiilrr\v.>rt (Tr.i.lcsr.iiili.-i) : the Ilireo-rpllrrl (.»arr nit scrnos. 



