1881. ] Zoology. 1005 
thrushes, and swallows, were seen around the light, and of these 
there struck the glass and killed themselves, one land-rail, one 
water-rail, four ring-ousels, and no fewer than 100 swallows. 
The larger birds do not often strike the glass in the revolving 
lights, but follow the rays. So far the observations show that all 
birds, with few exceptions, are migatory-——-even sparrows, which 
invariably leave Heligoland before the end of September. 
SuDDEN INTEREST IN JAPANESE OrntTHOLOGY.—In the report of 
.some difficulties encountered by a well known library in New 
York, in their efforts to meet the public taste, we find a reference 
to an ornithological work which is as new to us as the reported 
interest in that science is surprising. The Heradd says: 
“President P. said that the management has spent three dol- 
lars for standard works to every dollar that bas been expended 
on novels. The demand for the ‘ Birds of Japan’ was so great 
that the directors had to buy sixty copies; and for other costly 
works the demand exceeded the directors’ ability.” 
Perhaps one of the readers of “ Unbeaten Tracks ” may give us 
the means of properly classifying the ornithological specimen 
referred to.—W. H. Dall. 
AsiLus AND LiBELLULA.—So far as I am aware, robber-flies are 
not credited with capturing prey larger than themselves. But 
last August my attention was attracted, one day, by a medium 
sized dragon-fly fluttering on the ground, and looking closely I 
saw a robber-fly, about three-fourths of an inch in length, quietly 
clinging to his body just under the right fore-wing, and sucking 
his blood. Haste forbade my waiting for the end of the struggle, 
but the issue was not uncertain—¥ EZ. Todd, Tabor College, Lowa. 
SPECIMENS OF MELANTHO WANTED.—Sets of from five to ten 
specimens each, of all the species of the genus Melantho, from . 
every available locality. Please correspond with R. Ellsworth 
Call, 172214 Woodland avenue, Des Moines, Iowa. Liberal ex- 
changes will be given in Strepomatide or Unionidz. Material is 
wanted af once. Any specimens with the animal either dried or 
in alcohol especially desired. 
ZootocicaL Nores.—Some of the causes affecting the decrease 
in the number of our birds are discussed by Mr. H. W. Henshaw, 
in the Bulletin of the Nuttall Ornithological Club for October. 
Besides the effects of disease, accident, the attacks of other 
animals, which probably act as but a slight check in the increase — 
