762 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Among parasites, the Rhinantheae are distinguished, by the structure 
of the stem, the anther, the pollen, &c., from the allied Antirrhineae, and 
from the semi-parasitic Thesiaceae and Orobanchaceae. The Loranthaceae 
differ from the Thesiaceae in the nature of their vessels, and in the 
arrangement of their fibro-vascular system, as also from the Caprifoliaceae, 
Santalaceae, Olacineae, Ceratophyllaceae, and Chlorantlieae. From their 
anatomical structure the author separates the Misodendreae from the 
true Loranthaceae. The Cuscuteae differ from the Cassytheae in the 
habitual absence of stomates. The Cytineae, Rafflesiaceae, and Balano- 
phoraceae form a natural group from their anatomical characters. Further 
generic anatomical details are given. 
Among aquatic plants, the author separates Ottelia from the Hydro- 
charideae, to form, with Stratiotes and Enhatus , the type of a family 
characterized by its anatomy and by its anatropous ovules. 
Stomates occur (among parasites ) in Clandestina, in Hypopitys lanu- 
ginosa , in Monotropa uniflora , and in the greater number of the Loran- 
thaceae, Thesiaceae, and Rhinantheae. Medullary rays are wanting in 
some, but not in all parasitic Dicotyledones, as well as in many terrestrial 
and in most aquatic species. Details are given with regard to the 
presence of a general and of a partial endoderm ; and the occurrence of 
aeriferous lacunae similar to those of aquatic plants is noted in some 
parasites, as in the cortical parenchyme of Melampyrum, Bhinantbus , and 
Pedicularis , and in the woody substance of Cassytha. 
Sudden Changes of Form.* — Herr F. Hildebrand records the fol- 
lowing examples of sudden changes of form in plants: — (1) A seedling 
from an ordinary form of Juglans regia exhibited the form known as 
laciniata , with doubly pinnate leaves. It displayed an unusual sensi- 
tiveness to cold. (2) A plant of Hepatica triloba with ordinary 3-lobed 
leaves put up in two successive years leaves with a double lobing. 
(3) Two specimens of Bhamnus Frangula produced suddenly, but in one 
case not on all its branches, leaves which were deeply toothed or even 
lobed. 
Styles of Compositae. f — Mr. J. S. Chamberlain has made a compara- 
tive study of the structure of the style in different families of Compositae, 
especially in reference to the papillae and the collecting or brush-hairs, 
with a view to their usefulness for purposes of classification. He finds 
that, like other characters in the Compositae, those derived from the style 
cannot be used in all cases singly, but only in conjunction with others, 
in dividing the order into tribes. These characters are more constant 
and uniform in some tribes than in others. Thus in the Yernonieae, 
Eupatorieae, and Asteroideae, the structure of the style is very uniform 
and constant for each tribe, and can be used with great advantage. In 
the Helianthoideae and Cynaroideae the characters are still sufficiently 
constant to be of great aid ; while in the Helenioideae, Anthemideae, and 
Senecionideae there is less uniformity. Another difficulty is that where, 
as in some genera of Inuloideae and Helianthoideae, the flowers are 
dioecious, the brush-hairs are wanting on the style of the female 
flower. 
* Ber. Deutsch. Bot. Gesell., ix. (1891) pp. 214-8. 
t Bull. Torrey Bot. Club, xviii. (1891) pp. 175-86, 199-210 (4 pis.). 
