u 



10 



ESSENTIALS OF VEGETABLE PHARMACOGNOSY. 



borne, in the case of the willow, upon a 

 plant which produces no pistillate flow- 

 era. Fig. 12 illustrates branches (a) 

 crowded with male flowers, each (Fig. 13, 

 a) in the axil of a scale (b). In this case 

 the two modified leaves forming the 

 flower are entirely separate and the hol- 

 low portion of each (d) is small, borne at 

 the summit of a stem (c) and filled (Fig. 



minute 



14) with 

 rounded 



a great 

 bodies. 



number of 



These correspond, 



though of the other sex, to the macro- 

 spores which we have found the pistillate 

 flower to produce, and they are called 

 Microspores, in floweriug plants called 

 Pollen-grains. They possess the power 

 of germinating, growing and producing 

 Male Cells, comparable to the spermato- 

 zoids of animals, and requisite for the 

 fertilization of the corresponding element 

 produced by the mncrospores. The male 

 portion of a flower is called the Androe- 

 cium, frequently indicated by the symbol 

 A, and it consists of one or more Stamens, 

 in this case of two. As this flower con- 

 sists only of androecium it is known as a 

 Staminate Flower, indicated by the sym- 

 bol 6 



A vessel in which one or more spores is 

 developed is called a Sporangium, Macro- 

 sporangium, or Microsporangium. as the 

 case may be, and a modified leaf pro- 

 ducing sporangia is a Sporophyll. A 

 plant body bearing spores is called a 

 Sporophyte. When, as in this case, the 

 niacrospores are produced by one plant 

 and the microspores by another, the plant 

 is Dioecious. If in addition each plant 

 jjsproduced some perfect flowers it would 

 ^tbe Dioeciously Polygamous. If, as in the 

 .Alder (Fig. 15) pistillate flowers (a) and 

 : -staminate flowers (h), or, otherwise 

 .-stated, spore^i of both sexes, are produced 

 "by the same plant, it is Monoecious. If 

 r4n addition the plant bear some perfect 

 iflowers it is Monoeciously Polygamous. 

 \When, as illustrated in Figs. 22, 21, &c„ 

 the flower possesses both gyaaecium and 

 androecium it is Hermaphrodite, indi- 

 cated by the symbol 5 Hermaphrodite 

 flowers are not always perfect, as one of 

 jthe organs, while perfect in form, may be 

 functionless. Imperfect flowers present 

 pll intermediate grades between that last 

 mentioned and that in which there re- 



mains no trace of the lost part, or in 

 which it has even been transformed into 

 an organ of a different kind. 



The parts of the stamen and pistil will 

 now be named. 



Of the Stamen — Thf stem-like portion 



(c) regarded as corresponding to the petiole 

 of the sporophyll, is the Filament. The 

 portion containing the spores or pollen is 

 the Anther (d). The two halves of the 

 anther, each corresponding to a half of 

 the lamina of the sporophyll, are the 

 Thecae (sing., Theca) (Fig. 14, a). At an 



Fig. i6. 



earlier stage each theca is subdivided 

 into two Locelli (Fig. 14c), and In many 

 plants this condition persists to maturity. 

 The portion connecting the thecae with one 

 another and with the filament is the 

 Connective (b). Our detailed study of 

 the stamen, as of the pistil, may here be 

 anticipated by the statement that any or 

 all of their parts may in other flowers be 

 found modified in an extreme degree by 

 reduction, exaggeration or special form 

 of growth, and may bear appendages in 

 great variety, their true nature in many 



