1894.] The Influence of Mechanical Resistance. 151 
knife or saw from opposite sides of the cast down nearly to 
the plant organ enclosed. The halves were then easily 
broken apart without injury to the plant tissue. 
he cells were regarded as living or dead according as 
plasmolysis was present or absent after placing sections in a 
ten per cent. solution of potassium nitrate. 
The following plants were used in the experimentation: 
Allium cepa L Ligusticum Leguari, 
Althea tauriensis DC., Melianthus major L., 
Archangelica sativa Mill., Myrrhis odorata Scop., 
Caltha palustris L., Phaseolus multiflorus Lam., 
Cucurbita pepo L., Phytolacca dioica L., 
Dahlia variabilis W., Pterocarya fraxinifolia Nutt., 
usetum limosum L., Ricinus communis L., 
Eryngium lanum L., Sambucus nigra L., 
Forsythia viridissima Lindb., Triticum repens L., 
Helianthus tuberosus Be Urtica dioica L., 
ra 
a nig i; Vicia faba L., 
Us effusus L., Zea mais L. 
um garganicum L , 
Experiments and discussion. 
Here, then, with all the conditions of growth favor- 
istem ae ne space in which to extend, the primary mer- 
to rest 5 — its functional capability as it does when obliged 
found hd ow temperature or by insufficient moisture. Pfeffer 
© the 
ing three months in gypsum 
bases of many stems and about the rhizomes so as 
to incl 
ude the Z ; A 
| Hae 0 reparations 
Were examined f meristem. Some of these prep 
: five weeks afterward, some after eleven weeks. 
‘Le, p. 124. 
