1880.] 



MICEOSCOPICAL JOURNAL. 



189 



there is an abundant flora such as it 

 is— air plants, parasitic growths, 

 insectivorous plants, and strange 

 herbs seeking a livelihood in any 

 other way than the good old honest 

 one of growing from their roots. 

 It is this fact which makes the mi- 

 croscopical interest of botanical re- 

 searches in Central Florida. One 

 can scarcely examine with a two- 

 thirds objective the flowers, leaves 

 or stems of any plant growing there 

 without discovering some beautiful 

 or striking modilicatiou of plant 

 hairs, or scales, or glands, or other 

 absorbing or secreting organs. 



We will notice flrst the Onosmo- 

 dium as found in Florida — 0. vir- 

 ginianum. It grows from Virginia 

 south, but is more glandular I 

 think in Florida than any where 

 else. It will be almost the flrst 

 plant one would stop to observe on 

 entering the pine woods — a dark- 

 green, narrow-leaved, biennial herb ; 

 its straight stem of the second year's 

 growth, about a foot high, bearing 

 a raceme-like cluster of flowers, 

 coiled at the end, and straightening 

 out as the flowers expand. The 

 leaves of this plant are thickly stud- 

 ded on both sides with stiff trans- 

 parent hairs, lying nearly flat on the 

 surface, and all pointing towards 

 the tip end of the leaf. At the 

 base of each hair is a cluster of 

 glandular cells, amounting some- 

 times to fifty or more, arranged 

 in beautiful geometrical forms. 

 When pressed and dried in the 

 herbarium, the body of the leaf 

 turns to a dark green, almost black, 

 and on this back-ground, with a 

 half-inch objective, the hairs stand 

 out like sculptured glass, and the 

 glands like mosaics of purest pearls. 

 I think it is the most attractive 

 opaque object that can be shown 

 under the microscope. 



That these glandular cells, cover- 

 ing as they do nearly half the sur- 



face of the leaves, especially the 

 upper surface, and differing from 

 all other vegetable cells, subserve 

 an important purpose in the sus- 

 tenance of the plant, there cannot 

 be any doubt ; but just what that 

 purpose is, or what is the mode of 

 operation, I think, has never been 

 ascertained. 



In the same locality will very 

 likely be found the most beautiful 

 of all the croton plants, the C. ar- 

 gyranthemuTn. Unlike the other 

 Crotons, which are bushes, this is an 

 herb growing only about a foot 

 high, with a milky sap w^hicli ex- 

 udes when the stem is broken. The 

 leaves are silvery, verging in some 

 cases to a bronze color, and are 

 thickly covered on the upper side 

 with most remarkable and beautiful 

 stellate scales. The flower-buds 

 and stems when pressed, make 

 much more beautiful opaque ob- 

 jects than the leaves. 



The object of these scales is 

 without doubt, to prevent the too 

 rapid evaporation of the moisture 

 stored up in the plant. They are 

 the exquisitely woven blankets 

 which preserve the precious juices 

 so laboriously gathered. The same 

 kind of covering is spread over the 

 leaves and stems of all the air-plants 

 of Florida, and doubtless for the 

 same purpose. The well-known 

 Florida moss, although not a moss, 

 but a member of the pineapple 

 family {Tillandsia us7ieoides), is 

 an exceedingly beautiful object 

 under the microscope. Each hang- 

 ing stem is overlaid with filmy 

 white scales, every one of which is 

 fastened in its place by what would 

 seem to be the stamp of some min- 

 iature seal on golden-tinted wax. 

 This plant as ordinarily seen on 

 the live-oaks near cities, is a dirty- 

 looking and unattractive object, and 

 goes by the name of " black moss." 

 But in out-of-the-way places, re- 



