220 THE MICROSCOPICAL NEWS. 
centralized and kept tight by a paper adapter or collar made by 
the microscopist himself ;,but a small tube will only take a small 
ocular, and no other, so that the diameter of the body tube of the 
microscope should always be taken into consideration on the pur- 
chase of an instrument. 
To help our readers in the selection of a microscope with a body 
tube of such a size as will take the majority of oculars now made, 
we append a table of the various eyepieces, measured with vernier 
callipers to the one- -sixtyfourth of an inch. The measurement is 
also given of the neck of the ocular, over which the camera-lucida 
usually fits. 
Diameter of Ocular. 
Name of Vendor or 
Description of Model. Body. Neck. 
Maker. es 
inches & 64ths| inches & 64ths 
Powell & Lealand..| Large Stand......... | 
ee 4. Deck... 2. Natiowal’ (2 ...--te 1°17-64 57-64 
Smith & Beck...... Large stand .....:-.. 1°17-64 56-64 
Ross 86CO. 2i.0ds0. Ross-Jackson ...... 1'20-64 57-64 
Dig 9" Eos: Ross-Zentmayer ...) 1°20-64 57-64 
PPANCEL. esse ssesre farce stand :.--2%s-- 117-64 57-64 
STOW NING oe som «ap 2 Ordinary stand ...| 1°17-64 54-64 
“SL Re a Challenge -)2. 2% 1°13-64 56-64 
(SGM 2. Feces =. a PAgte VE oO senssonceee 1‘I7-64 
cones ececee sess: Premier (eo: eee 1°I4-64 54-64 
Witte” > Mz. piedents “tie... .: see * 
DAVAWAEG Pip ss. ntces Wonene @22-0275, 1'23-64 56-64 
PAKS eo pe. vee os oe SHA UUCT S06 ali eae 1° 7-64 i 
LEAS Soe ace teooe Gical liye. plein ace 58-64 i 
MCU ees oer a etree: SO ie: 59-64 ie 
Die t72i| ete 9 ee ees ior seh 16-64 = 
Upon those stands marked with an asterisk the camera-lucida 
is not made to fit in the ordinary way. 
INSECT DEVOURING PLANTS. 
By J. W. Goocu, M.R.CS. 
A paper read before the Windsor and Eton Scientific Society. 
NTIL comparatively recently, it was considered that one great 
difference between an animal and vegetable was, that the 
former had a stomach, and that into it food was taken there to be 
