168 
side of the spore-case is an elastic spring, made up of cells with 
thick radial walls. At maturity this spring, on drying, straight- 
ens out and bends backward, carrying with it most of the spores ; 
it then suddenly flies back to its former position, scattering the 
spores with considerable force. 
24. PROPAGATING BopIES (SPORES) OF A HorseTaiL (Egucsetum 
sylvaticum). 
Each propagating body or spore is furnished with two narrow 
appendages, called elaters; when dry, these appendages are 
straight, but when moist they coil spirally about the spore. The 
movements of the appendages under changing conditions of 
moisture help to scatter the spores. 
MarsHaLt A. Howe. 
OLD MICROSCOPES PRESENTED BY MR. C. F. COX. 
Mr. C. F. Cox, of the Board of Managers, has recently 
presented to the Garden eight microscopes to be added to the 
historical collection given by him in 1900 (see Journat for May, 
1900). The details of chief interest concerning the recent addi- 
tions are given below. 
The entire series, now consisting of twenty carefully selected 
instruments, includes several extremely rare stands and contains 
the principal types in the development of the microscope since 
The collection is exhibited in a case placed in the corridor 
in the western wing of the laboratories. 
No. 13. Jones’s “‘ Most Improved Compound Microscope,” the 
original model from which Nos. ro and 16 of this collection have 
been copied. With Martin’s revolving disc of six magnifiers, 
four other objectives, and all the other accessories catalogued by 
Adams, and some extras. All in flat mahogany case. Date 
about 1797. 
No. 14. ‘‘Drum-foot"’ Microscope, like one described in the 
Royal Microscopical Society’s Journal, April, 1899, pp. 213, 
214. Probably the model for Fraunhofer’s stand (1816) and 
for the popular French and German upright-tube microscopes. 
