VEGETABLE PHYSIOLOGY. 
381 
Why are they, though they slowly diminish in bulk, preserved during 
all the course of vegetation? and why do they not perish, like the 
leaves ? These reliections induced me to think that the bulb must 
have some important function to perform during the whole life of the 
plant, no part being given by nature without an intention.” 
After detailing several incidents which occurred during the Doctor’s 
investigations, he arrives at the following conclusion, viz. “ that solid 
bulbs or tubers are masses of starchy matter, provided by nature to 
serve as a support to the young plant, in the same manner as the 
albumen of the egg serves to nourish the chicken. 
“ Whether scaly bulbs and tubers are destined by nature to perform 
the same office I have not yet had sufficient experience to determine; 
but as they contain a mucilaginous or starchy substance, and have all 
the delicacy of texture mentioned; and as I have observed that the 
onion, while kept out of the ground, germinates, and continues to grow 
till it has reduced the bulb to a congeries of withered coats; that the 
Scillci, in a similar situation, will even dower; and that the tubers of 
3 the potato put out shoots, and nourish them for some time; I think,” 
continues the Doctor, “ it may be admitted, that not only solid bulbs, 
but also those that are scaly, are intended to nourish the plant with 
their substance.” 
It is to be hoped that Dr. T. will continue his investigations on the 
structure of all the varieties of bulbs, tubers, and other gross or deshy 
roots; he has the acumen of a philosopher, and no doubt his illustra¬ 
tions of the constitution, development, and reproduction of these curious 
vegetable bodies, would be a welcome addition to our present stock of 
botanical knowledge.— Ed. 
Vegetable Physiology. —This is a favourite topic with us; and, 
as it is a subject on many points of which considerable doubts are enter¬ 
tained, we, according to promise, feel it a duty to present our readers 
with extracts from the best authors who have written on this branch of 
botanical science, in order that they may be able, while observing the 
phenomena, to judge for themselves how far the published accounts 
and opinions agree with their own observations. 
The following are extracts from Dr. Lindley’s “ Introduction to 
Botany,” drst edition, (a second having been recently published;)—a 
book which not only contains all the knowledge acquired by its talented 
author, but also the marrow of all that was previously published by 
every botanical authority on the continent and elsewdiere. Concerning 
the “ elementary organs,” the Doctor proceeds: — 
“ Of these, the cellular tissue is the most important, as is apparent 
