44 



ESSENTIALS OF VEGETABLE PHARMACOGNOSY. 



the same time cell-division of its contents within the embryo-sac, it is designed for 



the production of true sexual elements, to 

 result in the formation not of a spore, but 



takes place, the combined changes consti- 

 tuting the germination of the microspore. 

 Through one or more of the perforations ^^ ^^ embryo, it is called in contradistinc- 

 of the extine already existing, or forcibly ^^^^ to tiie sporophyte or spore producing 



body, the Gametophyte. Nourishment is 



afforded partly by the contents of the pol- 

 len-mass and partly by the tissues with 

 which the prothallium is in contact. At 

 its lower end are one or more little bodies 

 which constitute the male clement and 



which are to fertilize the oosphere, which 

 we have already observed within the em- 

 bryo-sac. This fertilizing element is the 

 Male Cell, corresponding to the Anthoro- 

 zoid of cryptogams. The downward 

 growth of the male prothallium toward 

 the ovule is known as the Descent of the 



made by this process, protrude prolonga- 

 tions of the pollen contents, still enveloped 

 in a process of the intine. These process-^s, 

 or this process, for in general there is 

 but one, penetrates the tissue of the stig- 

 ma and extends downward through the 

 conducting tissue of stigma, style and 

 placenta, and is known as a Pollen-Tube. 

 A body of this kind, proceeding from the 

 germination of a matured spore, is prop- 

 erely to be regarded, like its female homo- 

 logue, as a plant body, distinct from that 



upon other surfaces which present the 

 proper conditions. It is known as a Male 



of the parent It is to be noted that it Pollen-tube. The distal end of the pollen- 

 can be equally produced by germination tube at length enters the ovarian cavity 



and finds the foramen of the ovule, con- 

 tact of the male cell with the oosphere is 

 Prothallium, and because, like the product effected and fertilization is completed. 



CARPOLOGY. 



Fructification or the Changes Produced by Fertilization. 



The changes effected by fertilization ex- 

 tend to all parts of the flow'er and even to 

 other parts of the plant. A consideration 

 of the objects of the process will prepare 

 us to understand the nature of ".he 

 changes. The objects are (1) the produc- 

 tion and maturing of one or more seeds, 

 including provisions for their protection 

 and nourishment throughout the process, 

 together with the nourishment of the parts 

 which thus protect them; (2) provisions 

 for their transfer, still enclosed in their 

 container, to a suitable place for germiaa- 

 tion and the fixation of the latter there, or 

 (3) pro's isions for their exit from such con- 

 tainer and (4) their transfer after such 

 exit to the place of germination and their 

 fixation there. The combined processes 

 connected with the attainment of thsf 



objects is Fructification, and the product 



thereof is the Fruit. 



It is clear that the energies of the plant 

 should not be called for in the further de- 

 velopment or preseryation of any parts of 

 the flower which are not serviceable as a 

 part of the fruit in the attainment of the 

 above named objects, unless possibly they 

 may possess some other function foreign 

 thereto, as, for instance, the action of the 



stamens of a flower in which fructification 

 has already begun, in fertilizing the ovules 

 of some other flower. We should there- 

 fore look (a) for the disappearance or 

 death of all floral parts not thus service- 

 able, and (b) for the stimulation and de- 

 velopment of those which are. That the 

 first of these two objects is an immediate 

 result of fertilization is strikingly and 

 unhappily illustrated in the behavior of 

 ornamental flowers, in which the latter 

 process is allowed to take place. Those 

 who produce for the market the handsome 

 and expensive flowers of orchids are 

 obliged to carefully exclude insects from 

 their greenhouses. Valuable flowers 

 which, without fertilization, would last for 

 several weeks, wither and die within a 

 few days, or even hours, after such proc- 

 ess has occurred. That the accomplish- 

 ment of the second named object is no less 

 immediate is apparent upon considering 

 the morphology of the fruit. 



The only portion of the flower which is 

 certain to be in no case utilized in fructi- 

 fication, and, therefore, to disappear after 

 fertilization, is the actual stigma, and the 

 stamens when they are non-adherent. 

 The starnens, as has been shown, may be 



