312 
POPULAR SCIENCE REVIEW. 
First contact with the penumbra, Aug. 12 
,, „ ,, shadow 
Middle of the eclipse . . . Aug. 13 
Last contact with the shadow . 
„ „ „ penumbra 
Magnitude of the eclipse (Moon’s diametei 
Mean time at Greenwich, 
h m 
. 9 22*5 p.m. 
. 10 42*6 
. 0 8*2 a.m. 
. 1 33-8 
. 2 53*9 
1) . 0*590 
First contact 109° from N. pt. of limb towards E. 1 
Last „ 157° „ „ towards W.f 
For direct image. 
BOTANY. 
The Grasses of Mexico. — M. Eugene Fournier has studied the Mexican 
grasses to such good purpose that he has raised the number of species to 638 ; 
whilst in the u Flora Mexicana ” of Kunth’s Synopsis only 88 grasses were 
recorded. He finds that 16 species grow under very varied conditions of life, 
extending from the littoral regions to the elevated plateaux. He also finds, 
as he had previously done in regard to the ferns, that many species grow 
on both slopes of the Andes, fie gives the following table showing the 
number of species peculiar to Mexico and common to it and other regions: — 
Peculiar to Mexico 376 
Common to Mexico and Texas 32 
„ „ „ the United States ... 60 
„ „ ,, the Antilles .... 98 
„ „ „ the Tropical region (north of 
Brazil and inch Trinidad) . 102 
„ „ „ the Andes .... 28 
„ „ „ Brazil 98 
„ „ „ the Argentine Republic . . 22 
„ „ „ the Old World. . . . 33 
The peculiar species are very numerous and include nearly all the Mexican 
species of the genera Stipa , Aristida, Mecklenbergia , JPereilema , Lycurus , 
Epicampes , Deyeuxia , Trisetutn, and Bromus. They are related generically 
to the species of the Andes of South America. Fifteen genera, out of 173, 
belong exclusively to Mexico and eleven of these include only a single 
species. 
Out of 262 species common to Mexico and other regions only two grow in 
California. East of the Rocky Mountains, Texas has 32 species ; one grows 
in the prairie region, and the other 59 United-States species are almost con- 
fined to Florida, Georgia, and South Carolina, scarcely any occurring in 
Louisiana, Mississippi, or Alabama. The cause of this peculiar distribution 
may be found in the direction of certain winds, especially the whirlwinds 
noticed by M. F. F. Hebert, which, descending upon the Gulf of Mexico by 
the Valley of the Rio del Norte, strike the North of Florida and then sweep 
northwards along the eastern slope of the Alleghanies. 
By their geographical distribution and botanical characters the Mexican 
