172 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
cattle, and in tbe hair along tlie flanks. After some time it was found 
to be identical with Hsematohia serrata Eobineau Desvoidy, from the 
south of France ; it is suggested that its vernacular name should be 
“ Horn-fly.” It is distinguished from the common cattle-fly by its 
smaller size, and more especially by its long palpi ; it lias for its imme- 
diate allies some of the most vexatious of flies indigenous to various 
continents. It is very probable that the largest number of cosmopolitan 
insects are found among the Diptera, for they furnish the greater number 
of our domestic pests, and their eggs or larvae are constantly mingled with 
our food-material or common objects of commerce. Musca domestica 
abounds even on the uninhabited plains of America. Some of such 
species are not, however, importations to America, as the Colorado 
Beetle and the Hessian Fly are sufficient to bear witness. Of the para- 
sitic family of bot-flies, it is probable that all the (eight) species common 
to Europe and America have been introduced into tlie latter with the 
domestic animals, with the exception of the circumpolar reindeer bot-fly. 
Anatomy of Ant-Lions.* — Dr. F, Meinert gives an account of his 
examination of the digestive tract of some larvae of Myrmeleon which he 
found in Algeria. The mouth is not, as Hagen supposed, closed, but is 
merely compressed. The stomach is completely closed posteriorly, and 
the first part of the small intestine is a compact mass, with no lumen. 
There are eight Malpighian vessels, two of which are free, while the 
other six are connected with the small intestine ; these vessels are ordi- 
narily converted into silk-secreting glands, and the swollen part of the 
c8Bcum becomes the reservoir for this secretion. The remnant of the 
food of the larva is collected in the stomach, and is not expelled till 
the creature becomes a perfect insect; it is made up of an internal 
amorphous mass and an outer layer which contain phosphate of calcium 
and a large quantity of uric acid. 
Prosopistoma variegatum.f — M. A. Yayssiere gives an account of 
some larvae of this species, which was regarded by its discoverer, 
Latreille, as an insect. These larvae were aquatic and somewhat ad- 
vanced in development, as the possession of wings showed. The species 
is much larger in size than its European congener, and the author was 
able, therefore, to extend his anatomical studies. There are six pairs 
of tracheal gills in the large respiratory cavity which is situated beneath 
the posterior half of the carapace ; but the sixth, which are wanting in 
the European form, are much reduced, and cannot take any active part 
in respiration. As there are six abdominal segments and four caudal, 
we have the ten rings which are found in all larvae of other genera of 
Ephemeridae. 
Studies in Pond Life.J — Mr. C. M. Weed gives an account of some 
rather scattered observations on a series of particularly rich ponds in 
Ohio. The first deals with the life-history of the larger Typha-borer 
[Arzama ohliquata ) ; the larva, which is rather handsome, and swims 
readily by an undulating snake-like movement, is especially interesting 
on account of the peculiar 'position of two of the spiracles, which are 
* Overs. K. Danske Vid. Selsk., 1889, pp. 43-66 (2 pis.). 
t Comptes Rendus, cx. (1890) pp. 95-6. 
j Bull. Ohio Agricult. Experiment Station, i. (1889) pp. 4-17 (2 pis.). 
