516 ANSWERS TO CORRESPONDENTS. 
Hanaman and others. They have already vindicated their name in this 
sense as well as at home. 
r. Charles Stodder, of the Boston Optical Works, exhibited Cutter's 
rn microscopes, and Tolles’ students’ microscopes, of various degrees 
f comp 
them. In buying a students' microscope, however, the beginner should 
always be advised, in the writer's judgment, to have it —€— witha 
first class l-inch objective or something very near it. So much of his 
early work is, or ought to be, done with this power, and his success as 
well as pleasure depends so much upon its light and ae that it 
ought to be the last point economized upon. The sliding stage upon some 
of these instruments would seem to be easily convertible, for those inim 
wish it, into a White's lever stage. 
Mr. F. Miller, of New York, exhibited a good students' microscope of 
very low cost. It is chiefly ewe for its large body, which admits à 
large ions piece and gives a good r. Miller also exhibited excellent 
illuminating prisms and various accessories and objects, including Mól- 
ler's beautiful type pla 
Crouch's educ E rhet abs had a larger body than even Miller's, 
admitting the use of the same eye-pieces as the first class stands: e 
y Swift of 
eme was exhibited by Dr. Ward. Also Murray and Heath's *sea- 
side. 
Of the general business of the subsection the most important was the 
appointment of a committee to report in relation to uniform standards in 
the power of a; eye-pieces, etc. President F. A. P. Barnard of 
New York, Mr. E. Bicknell of Cambridge, apes ss., Dr. R. H. Ward of 
Troy, N. Y., Professor C. E. Pickering of Bost s Prona r O. N. Rood 
of New York, and Dr. Josiah Curtis of Plum. diese di this committee. 
Oe 
ANSWERS TO eS E 
oo. 4h d e Humming Bird you describe is the male of the common Ruby- 
throated H e Bird erre moi L.) The female and "cs eru are without 
the yy eek rlet color on roat seen in the males fter midsummer the 
paoata throated individuals are d Rd numerous thon the baies There is but one 
species of Humming Bird in the Northern States. — J. A. A 
J. M. J., Halifax.— We will endeavor to name the collection of marine invertebrates 
you 
8: A. W., Bucks eos Pa. — Your fern is Osmunda regalis. —J. L 
S. L., Freehold. N. J Piola: con hag fos is eg pa ees rape Surak, which was in- 
troduc ed Ears Togian and t 0 Quebe aa R statea to to de estroy annually 
cabbages in de lreid da m city. It thence spread into 
New ots and is now common about New York. d Philadelphia. It feeds con- 
€— on the heart of enden ere | yiee the two other species of Pieris, P. Protodice 
virak pia orn -— yd upæ of a ies of Syrphus fly, which feeds.on the 
plant. lice, Sca d wir on the ses in dio saiem Tihe 8 yrphus fly is of course 
