1896.] Recent Literature. 731 
other causes, i. e., to physical, chemical and mechanical pecu- 
liarities of the soil (Hiltner’s account). Dr. Hiltner’s own ob- 
servations date from the discovery of a browning of the root 
hairs. Hestates that often in his germination experiments he 
had observed that a part of the root hairs on certain seedling 
beets would be colored brown and peculiarly shortened. When 
examined under a hand lens these hairs were seen to be mere 
brown points instead of long tubes. Seeds from a lot which 
germinated well, and produced seedlings that showed this 
browning of the root hairs to a marked degree, came up badly 
when planted in garden earth, and those which did grow after- 
wards developed the root-burn, the characteristic constriction 
occurring just where the sound root hairs were wanting. Hell- 
-riegel’s treatment was repeated. After soaking the beet balls 
in a solution of carbolic acid the root hairs remained perfectly 
sound, and there was no subsequent root-burn. The parasite, 
however, is not a fungus but a bacterium. “In each epidermal 
cell of the root which bore a stunted hair there was to be found 
a specific bacterium, and to this is to be attributed the final 
destruction of the root.” It is not stated whether the organism 
was isolated from the roots, or whether any infection experi- 
ments were undertaken. The context would lead one to think 
nothing of this sort was attempted. 
RECENT LITERATURE. 
Journey Through Mongolia and Thibet.'—This volume is 
413 pages, is published in octavo form under the auspices of the Smith- 
sonian Institution. It is an account of the travels of Mr. Rockhill in 
Mongolia and Thibet, based on a diary kept during the journey. The 
variety of subjects touched upon by the author in his descriptions of 
the country traversed, and the people with whom he was brought in 
contact, gives this volume a peculiar interest. Appendices to the diary 
‘ Diary of a journey through Mongolia and Thibet in 1891 and 1892. By Wil- 
liam Woodville Rockhill. Published by Smithsonian Institution, 1894. 
