ITS NATURE AND PARTS. 



167 



303. The Torus, or Receptacle of the flower, also named 

 THALAMUS, 1 is the axis which bears all the other parts, that 

 upon which they are all <* c 

 (mediately or immediately) 



inserted. These are all ho- 

 mologous with leaves. This 

 is extremity of stem, or 

 floral axis, out of which the 

 organs described grow, in 

 succession, like leaves on 

 the stem ; the calyx from 

 the very base, the petals 

 next within or above the calyx, then the stamens, finally the 

 pistils, which, whether several or only one, terminate or seem to 

 terminate the axis. (Fig. 316.) 



304. Metamorphosis. If flower-buds are homologous with 

 leaf-buds, and the parts of the flower therefore answer to leaves 

 modified to special functions (293), then the kind of flower here 

 employed in explaining and naming these parts is a proper 

 pattern blossom. For the organs are all separate pieces, 

 arranged on the receptacle as leaves are on the stem, the outer- 

 most manifestly leaf- like, the next equally so in shape, though 

 not in color, the stamens indeed have no such outward resem- 

 blance, but the ripe pistils open down the inner angle and 

 flatten out into a leaf- like form. The adopted theory supposes 

 that stamens and pistils, as well as sepals and petals, arehomolo- 



numerum," etc., and so elsewhere, besides founding his orders on the num- 

 ber of pistils. Among even French authors, Mirbel (1815) writes, "Le 

 nombre des pistils n'est pas le meme dans toutes les especes," &c. Moquin- 

 Tandon freely refers to pistils in the plural, and Aug. St. Hilaire takes 

 wholly the view here adopted, distinguishing the solitary pistil into simple 

 and compound. DeCandolle, in Theorie lementaire, third edition, writes, 

 " Chaque carpel est un petit tout, un pistil entier, compose' d'un ovaire, d'un 

 style, et d'un stigmate." Of English authors, no other need be cited than 

 Robert Brown. The terms in question, then, are : 



Gyncecium, the female system of a flower, taken as a whole. 



Pistil, each separate member of the gynoecium; this either simple or 

 compound. 



Ovary, the ovuliferous portion of a pistil. Substituting a part for the 

 whole, this term is often used when the whole pistil is meant. 



Carpel, or Carpid, or Carpophyll, each pistil-leaf ; whether distinct as in 

 simple or apocarpous pistils, or in combination of two or more to form a com- 

 pound or syncarpous pistil. 



1 By Tournefort, and adopted by Ludwig. Receptaculum jlaris, Linnaeus. 

 Thorns, Salisbury. Torus (the proper form), DeCandolle. 



FIG. 316. Parts of the flower of a Stonecrop, Sedum ternatum, two of each sort, 

 and the receptacle, displayed: a, sepal; b, petal; c, stamen; d, pistil. 



