76 ANTHER. 



be undistinguishable from one, but for its bearing an anther. 

 In the Water-lily it is found in every degree of development, 

 from its common form to a petal, showing the true nature of the 

 stamen, that it is a modification of leaves. In the Carnpanula 

 the lower part of the filament assumes the form of a fleshy scale. 

 Although generally smooth, still in some plants, as in the 

 Tradescemtia, it becomes in some parts covered with hairs. In 

 the Thalictrum it is thickest at its summit, and is said to be 

 clavate. Sometimes the filaments are united together with the 

 style into a solid column, under the name of columna or gyno- 

 ategium^ as in the Asdepiadce. 



122» The anther is generally composed entirely of cellular 

 tissue, and consists of two lobes^ united by a connectivum, and 

 filled with pollen. The connectivum corresponds to the midrib 

 of the leaf, wdiile the lobes are formed by its lamina, folded so as 

 to form its cells. The variations in the form of the anther are very 

 numerous. The true type of the anther, then, is two lengthened 

 parallel cells (connected together), opening by a longitudinal 

 suture corresponding to the margin of the leaf of which the an- 

 ther is composed. It sometimes happens that the septum is 

 absorbed or not developed, when it is one-celled; at other times 

 one half of the lamina seems not to be developed, and a one- 

 celled anther is the result, as in the Cuima. Sometimes the con- 

 nectivum spreads out at its summit, and the lobes, instead of being 

 parallel, assume every degree of inclination. In the Monarda 

 they are at right angles, and should the points of the lobes grow 

 together we have a one-celled anther from this cause. In the 

 Sage but one side of the connectivum bears an anther, the other 

 side being very diff'erently developed. 



It sometimes happens that the anther is more than two-celled. 

 This is occasioned, in some cases, by the folding inwards of the su- 

 tures, so as to form a union with the back of the cell, as in the Ash. 



The Cucurbitacece present a curious modification of the an- 

 ther, in which they are long, narrow, and sinuous, and folded 

 back upon themselves. 



123. When the anthers are attached by their base to the 

 summit of the filament, they are said to be innate ; when by 

 their back, adnate. When they seem to be balanced on the top 

 of the filament, they are said to be versatile. The anthers of 

 grasses are versatile. When the anthers are turned inward, 

 they are said to be introrse, and when turned outward, extrorse. 



In the water-lily? — 122. Describe the anther. What is the true type of 

 the anther? Wlien one-celled? How in the sage ? — 123. When are an- 

 thers innate? When adnate? When versatile ? When introrse? When 

 exirorse ? 



