122 



THE STAMENS. 



of communication between the pollen upon the surface of the pistil and the young 

 embryo. It is presumed that some undetected material is con- 

 veyed through the tube, which is the immediate source of ferti- 

 lization ; and it has been observed that the flower has begun to 

 fade immediately after this occurrence, as though the function of 

 that organ hau then ceased. 



How swnute and wonderful are the structures and their 

 functions found in vegetables ! equally so with anything known 

 in the animal creation. Thus all the parts of a plant, external 

 to the stamen, are created in perfect subserviency to the func- 

 tions of that organ ; and of the stamen itself, how small a portion 

 seems to be essential. The filament supports the anther, the 

 anther incloses the pollen, the cell- walls of the pollen inclose a 

 little matter, and it is only a part 

 of that ultimate production which 

 is essential to the function for 

 which the' plant was chiefly 

 created ! 



Before leaving this part of our 

 subject we must refer to a sub- 

 stance lying between the true 

 stamen and the pistil, and which 

 is considered to consist of unde- 

 veloped stamens. It is known 

 as the disk (Fig. 241 <?), and 

 appears under various forms, according to the so-called superior and inferior positions 

 of the ovary. In the Compositse and Umbelliferae, with their inferior ovary, the disk 

 is a fleshy body, placed upon it, and oftentimes assumes a scaly appearance. In 

 others, as the Dead-nettle and other labiate plants, it is found beneath the ovary, and 

 has some resemblance to glands. As it is a mass of undeveloped stamens, its position 

 will always be below the ovary, although it may adhere to that organ, and seem to be 

 perigynous or epigynous. 



HIT. 232. Pollen tubes, 

 passing fajmtte pol- 



conducting tissue in 



Fig. 253. Pollen tubes in the 

 CEnothera bienn-is. 



Fig. 234. Grains of Pollen ; a, Fuschia ; b, Scirpus romanus ; e, Sal via; d, Armeria fasiculata ; 



e, Acacia. 



The Pistil. The pistil is the female part of the flower, and the central point 

 around which all the organs placed upon a branch are arranged. It is usually 

 a complex organ, and oftentimes compounded of many leaves. It is readily distin- 

 guished by its central position, and the dissimilarity between it and the stamens in 

 height and form, and more particularly by the absence of an anther at its apex. Occa- 

 sionally it puts on a foliaceous appearance, as in Fig. 235. 



