20 



ESSENTIALS OF VEGETABLE PHARMACOGNOSY. 



great importance iu diagnosis and classi- mulciforui Hppearances which those 

 fication but of such physiological impor- organs present in the extensive flora 



tance that they constitute a distinct or- 

 gan of the flower from that point of view. 

 The peculiarities of structure and secre- 

 tory function of glandular tissue will be 

 considered iu the part relating to his- 

 tology. Here we note that although 

 glands are sometimes distributed through 

 the other tissues in such a way as to be 

 imperceptible on superficial examination, 

 their tissue is at other times collected 

 into more or less conspicuous bodies of 

 definite form and position. The term 

 **Gland" is frequently applied also to 

 bodies which resemble glands in location 

 and form, but which are not glandular in 

 function. Glands may be stalked (Fig. 

 53, a), sessile (Pig. 54) or depressed (Fig. 

 55, see Nectary), and they may develop 

 upon various parts of the flower. Those 

 npon the outside of the calyx are exten- 

 sively utilized in classification in the nat- 

 ural order Malpighiaceae, while those 

 upon the inside are so used in the order 

 Apocynaceae (Fig. 56) and Gesneriaceae. 

 Fig. 55 is an illustration of glands lo- 

 cated upon the corolla, while Fig. 57 illus- 

 trates them connected with the stamens, 

 as seen in Sassafras. 



Glands upo-n filament-like stalks, suit- 

 ably located, may easily be mistaken for 

 stamens, (Jlands may themselves be ap- 

 pend aged. 



The misleading efiEects of suppression 

 have been observed in the Hepatica (Fig. 

 22) in the absence of th^ corolla, the 

 metamorphosis of the calyx toward corolla 

 and of the epicalys toward calyx. Those 

 of abortion are seen in the Pulsatilla (Fig. 

 16), where the petals b and c are reduced 

 to simulate sterile filaments. 



Exaggeration of growth is well dis- 

 played in the torus of the starawberry and 

 the placentae of the watermelon, which 

 respectively contribute the massive edible 

 portions of those fruits. 



The principles of anthology having thus 

 been followed into and through the typical 

 flower, and the general nature of the 

 deviations therefrom having been outlined. 



from wliicK our drugs arp derived. 



That division will not, however, close 

 our consideration of flower structure, as 

 some important modifications will remain 

 to be discussed in our chapter on pollina- 

 tion and fertilization. 



THE PtRIGONE. 



The perigone is to be studied as to the 

 number of its circles, their color, text- 

 ure and surface, the number of parts 

 forming each, their adhesion or cohesion, 

 the form and divisions, if any, of each 

 and of its parts, appendages, secretions, 

 metamorphosis or other variations, ar- 

 rangement of the parts in the bud, move- 

 ments or other noteworthy habits and 

 duration. The normal condition of two 

 circles, and its modifications through 

 abortion, suppression, duplication and 

 metamorphosis, and their agreement with 

 the numerical plan of the flower and 

 its modification through the same in- 



F 



fluences, need no further discussion. 

 The typical idea of a calyx more or 

 less herbaceous and a corolla thin, deli- 

 cate and brightly colored, is not always 

 realized. In the Crocus and most re- 

 lated flowers the parts of both circles are 

 similarly petaloid. The petals of Gar- 

 cinia are thick and fleshy, in Caopia they 

 are leathery and in Alzatea hard and al- 

 most wood-like, at least when dried. The 

 surfaces of the sepals, particularly the 

 outer, are not commonly glabrous, while 

 those of the petals are; but even the lat- 

 ter are often glandular, pubescent, densely 

 woolly, or even prickly (some species of 

 Solanum). No shade of color is denied 

 to the perigone, nor is the color neces- 

 sarily uniform among the parts of the 

 circle or even over the surface of any one 

 part The shade and markings are very 

 liable to vary in different individuals of 

 the same species (varietal or formal va- 

 riation), so that color is not always a 

 good character on which to base a deter- 

 mination. In general the color deepens 

 as the altitude of the habitat incr 



r*^^* 



wA QV-aU , .-^ c^^A *- 'A .- I ^^^ number of parts entering into either 



we shall pioceed to a consideration of „^,,v.... .i.... 1v...k.. .y.J^ .^,v. ;. . 



perigone circle, whether these exist in a 



the several parts of the flower, with the distinct or a coherent state, is indicated 

 object of preparing us to interpret the by the appropriate numeral preceding the 



