SCIENTIFIC SUMMARY. 
313 
Graminese are divided very clearly into two groups — those which are peculiar 
to Mexico or common to it and the Andean region, or to more northern re- 
gions, are generally distinguished by the slenderness and lightness of their 
leaves and panicles ; those which spread into the tropical region, on the con- 
trary, are remarkable by their size and the amplitude of their organs of vege- 
tation and of their inflorescence. The former generally inhabit dry and 
mountainous localities; the latter the banks of rivers, and moist places. 
Some of them extend from the United States to the Argentine Republic, 
through 70° of latitude. — ( Comptes renclus, June 10, 1878.) 
The Influence of Moisture on Vegetation. — Dr. Paul Sorauer has made 
some experiments with spring barley which led to the following results : — 
In dry air branching was greater than in moist, the mean figures standing at 
2 * 77 and 2*37 respectively ; the length of leaves was greater in moist air in 
the ratio of 21*37 to 21*07, but the breadth was less (6*74 to 7*33). A 
moist atmosphere is more favourable to length of leaf-sheath in the pro- 
portion of 9*26 to 8*18, to the growth of the principal stem as 13*5 to 11*5, 
and to root-development as 26*8 to 23*9. The epidermal cells of the leaves 
were more numerous and broader, the cells between the stomata shorter, and 
the stomata themselves shorter in dry air. Leaves developing in a moist at- 
mosphere have fewer stomata per millimetre of length. — (Bot. Zeit. January, 
1878, and Journ. of Botany , March 1878.) 
The Fungi of the Vine. — The study of the fungi infesting the vine is 
one of considerable interest, not only to the scientific botanist, but also in a 
high degree to all interested in the cultivation of the vine. Baron G. Felix 
von Thiimen has published an elaborate monograph upon these parasites, con- 
taining an enumeration of no less than 220 species of fungi which occur upon 
vines in various parts of the world. The fungi are distributed as follows 
upon nine species of the genus Vitis: — V. vinifera, Lin., 150 ; V. Labrusca, 
Lin., 54 ; V. cestivalis , Mich., 13 ; V. vulpina, Lin., 7 ; V. riparia, Mich., 3 ; 
V. cordifolia, Mich., 3 ; V. rotundifolia, Mich., 3 ; V. caudicans, Engelm., 1; 
and V. sylvestris, Gmel., 2. The fungi affect the leaves, fruit, stems, branches, 
and roots of the plants. Nineteen fungi affect the grape itself, and of these 
Oidium Tuckeri is the most important from an economical point of view. 
Baron von Thiimen appears to follow Fuckel in regarding it as the conidial 
form of Splicer other a Castagnei, Lev., and therefore distinct from the American 
Erysiphe nectator, Schw., which species does not seem to have been recorded 
since Schweinitz’s time ; while it is classed by Dr. Cooke, in u The Erysiphei 
of the United States ” among the “ species dubiae.” Baron von Thiimen also 
considers it unconnected with a variety of TJncinula spiralis , B. and C., which 
sometimes occurs upon the grape in the United States. 
Among the great number of fungi infesting the living and dead stems and 
branches of the vines there are many new species. Of the Hymenomy- 
cetous fungi, twenty-two species are mentioned, mostly occurring on the 
dead stems ; these include a small agaric from the Cape of Good Hope 
( Agaricus proteus, Kalchbr.) allied to Ag. variabilis, P. One of the 
most interesting of the fungi on living vine-leaves is a new species of 
TJredo ( U. Vitis, Thiirn.), which, like Feronospora vitis, is of transatlantic 
origin. 
The difference between the American and European vine-flora is very 
