The preparation and treatment of woods for microscopic study* 
Forest B. H. Brown 
(WITH SIX TEXT FIGURES) 
CONTENTS 
PAGE 
Bs INTRODUCTION (05) fi gc so Che ee ea eae ees 127 
SUANIOSIMENT OF MICROTOME (© 600 ye eae eee gp a ke ag) 129 
3. PREPARATION OF MATERIAL FOR SECTIONING .......-..-0-0-ccucecvcecece 132 
BC CULLING THE BOOCKS (0075 44 oo ee ee ee. 132 
By REMOVING (SAE BER er gs cate eS et ts eae ree dee rl pees 133 
Ci; BOR TERING (THE TISSUM Ss |) Oia ees oa et ee es pee 133 
Disc TOBIN ridin ease aca ei Pues ait Ee Lk ote i bd CS Gece 135 
Ee SECTIONING WITH. THE MICROGTOME 23.05 6s 25 ln oe cc Nh 136 
HARD GRETIONS ho sta) oar eee AP tear gs 5 ok By 137 
4. bikinis OF Anat BP IAACERATION SS ig ho eee er as 137 
S--LERINITION OF ANATOMICAL DETAIES) 3) 20550 tissy Bh Fee a. 138 
EERE STAINES 5 oat OMe es ei RG Lh We ae ig 138 
B. DUE RD ENTIAL GUVRNCTION 0p wie fi ee Pea ee i eG I4t 
6. ccknath eis ee ee ee ee I4I 
: Pi CREE CLO S re ea a a ite, Eis ee ae 141 
els MSIE SO CRNBr SEG NR ct een hing aie ete A haere chk Waimea dds cw ig bay ate 142 
GUMS ei es rede geete teh cats Ok suc Ve eas ed aces 142 
D. ESSENTIAL OILS, RESINS, AND GUM-RESINS..........5..-0¢0 ce ceeus 146 
ee PAE Ne ae eo M Ee hice cee ound Os Mey Ms SEE eas wala woe 146 
Bris ENING oc. er ae oe NPR Sage Way See tg Me ah lar ges yeu Dy 4 aun pew 6 @laay 146 
ee eh, CRUSE RE Sy eee pas eta g Wits ok pile b Woe Ge viele ob 146 
HO CHRMICAL (GROWTH -RINGS oe ey Sie tLe ee eos Sele bee ane 147 
PROG EC RMMIRATION LEST. eo ig eo oy ee os ke eve 148 
er (Sita rem pee ee ee ea os a eg ae pa aye 149 
1. INTRODUCTION 
By reason of extreme variation in the mineral, resin- or gum- 
like content, and in the texture, hardness, and other properties 
peculiar to the stem tissues of tropical woody plants, the task of 
preparing these for microscopic study is ordinarily a difficult one, 
particularly in the case of an extensive series composed of numerous 
unrelated species of widely differing ecological types. The pub- 
lished technique relating to the preparation of wood for slides has 
been worked out primarily from a study of the comparatively soft 
* Contribution from the Osborn Botanical Laboratory. 
127 

