124 GEOLOGY. 
known as Ægeriæ acerni Walker (Trochilium acerni Clem.).— 
GC. V. RILEY, St. Louis, Jan. 20, 1874. 
Tue Anatomy or Worms.—Claparéde’s elaborate posthumous 
work with fifteen plates, on the anatomy of the sea worms, appears 
in the “ Mémoires de la Société de Physique et d’Histoire Naturelle 
of Geneva. ; 
' GEOLOGY. y 
Tae N. W. Wromine Exrepition. — The summer of 1873 isi 
noted for the number of expeditions which were organized for the 
purpose of explorations in the territories, and the almost uniform — 
: success which has resulted, from a scientific point of view. Among 
all of these none has perhaps attracted so little attention as the 
small band which quietly set out from Omaha on the second day of — 
last June, with the purpose of accomplishing, with the smallegt pos- 
sible appropriation, what three successive parties, led by the most 
intrepid and daring explorers of the western country, had Pe 
nounced impossible. 
This expedition, ina tour of some set or nine hundred miles, : 
made a careful topographical, geological and botanical survey of a 
large portion of unexplored territory in N. W. Wyoming, adjacent — 
to the Nationgl Park, and connected the whole with the work 
previous explorers by a complete reconnoissance of the park itself 
The principal geological results have already been’ published a 
outline,* and the writer has prepared a\paper for the NATURALIST, 
relating more especially to the features of the Yellowstone Park, 
I must therefore. content myself, in this place, with a very Di 
account of the most important results of the expedition. 
a - Besides the unravelling, in a great measure, of the compli 
= -mountain system of the great central water-shed of North Ame e 
oe the head waters of the three great rivers. which here diverges 
ee from a focal point,+ were explored and mapped, and several ni 
~ passes were discovered, through the rugged walls of the Si 
Shoshone} mountains. After a successful tour of the whole 
reserved. tract, | luring which ample collections were made 
ended the valley of the Upper Yellowstone River, 
— Water” of Lewis and Clarke, which 
. the 
covering the “Two 
