1873.) 311 [Stodder. 
Dr. Perkins made many original investigations on the 
light of the stars and comets, and of the Aurora Borealis. 
He also was engaged in the study of microscopic animals 
and plants, which occupied his attention at the time of his 
death. These studies were pursued from the pure love of 
science, and entirely free from ambition, Dr. Perkins rarely 
published his results. He was twice elected President 
of the Mass. Medical Society, and was a Fellow of the Am. 
Academy of Arts and Sciences, and one of the trustees of 
the Peabody Academy of Science, at Salem. 
Dr. Brewer exhibited a pair of rare buntings from Cal. 
(Plectophanes maccownii), presented by C. E. Aiken, Esq,, 
to whom the thanks of the Society were voted. 
Section of Microscopy, March 12, 1873. 
Mr. Bicknell in the chair. Twelve persons present. 
Mr. Bicknell exhibited the formation of crystals of silver 
under the microscope in a very simple way. A small quan- 
tity of a solution of nitrate of silver in water is placed ona 
glass slide, and into this liquid a few small pieces of copper 
wire are dropped. Crystals of silver begin at once to form, 
creeping across the field of view in a very beautiful manner. 
When the crystalization has proceeded far enough the pieces 
of copper wire may be removed, and the crystals of silver 
gently washed on the slide, and, after being well dried, can 
be mounted either dry or in balsam as permanent objects. 
Mr. Stodder read a paper by Dr. Pigott in the Monthly 
Microscopic Journal for February, on the scales of the Lep- 
isma saccharina, and exhibited scales with Tolles’ objectives 
74, and immersion 4 and 7, with oculars A and 3. 
With the 54, objective the scales showed the appearances which 
formerly were the test of the best instruments; with the 4, the black 
ribs were sharply defined, with light beads in the interspaces. ‘The 
zis showed admirably all the various appearances described by Dr. 
Pigott, with many others; in fact, almost every one present saw some- 
thing different from the others, or else described the same appear- 
