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On the Structure of the Raphides of Cactus enneagonus. By 
John Quekett, Esq., Professor of Histology to the Royal 
College of Surgeons of England. (Read Jan. 28, 1852.) 
Every living being that is made up of parts or organs, each 
having a definite structure, and performing a certain office, is 
termed an organized being ; and the materials, however com- 
plicated, of which it is composed, are termed organic matter. 
The components of the Mineral Kingdom, on the contrary, 
possessing little or no structure, but generally being homoge- 
neous throughout, and having no adaptation of parts to per- 
form separate functions, are called inorganic or inorganized. 
If organic matter be subjected to chemical analysis, it will 
be found that in the first stage certain compounds, termed by 
some chemists proximate principles, or organic compounds or 
organizable substances by others, will be obtained ; each of 
which principles, by further or ultimate analysis, will yield 
simple elements. Thus, for instance, from the organized sub- 
stance termed muscle we obtain by analysis, first, fibrine, a 
proximate principle, which is its chief constituent ; and, sub- 
sequently, by the analysis of fibrine, we get the principal 
elements — oxygen, hydrogen, carbon, nitrogen, and sulphur 
in certain proportions. If, however, a mineral, or inorganic 
matter of any kind be subjected to analysis, we get no proxi- 
mate principles, but only simple elements. Organic matter 
may be found in two states, viz., in that of life or in that of 
death. Living matter possesses the powers of growth and 
integrity, may select from surrounding materials, and appro- 
priate to its uses the inorganic elements ; but in the state of 
death these powers are destroyed, and decay is the natural 
consequence. 
It is to the nature of this organic basis or matter of plants 
that I would now direct your attention, leaving that of animals 
for future consideration. 
In commencing our examination with the vegetable king- 
dom we shall find that inorganic or earthy matter exists in 
plants in two states, viz., 1st, as crystals, termed raphides, 
occurring in the interior of cells, and 2nd, in intimate con- 
nexion with the organic basis of the plant — in this last state 
the inorganic element chiefly consists of silica. 
If we examine a portion of the layers of an onion or of a 
squill, or by taking a thin section of the stem or root of the 
garden rhubarb, we shall observe many cells in which either 
bundles of needle-shaped crystals or masses of a stellate form 
occur ; these are termed raphides, from the Greek Patptr, a 
needle, the first crystals discovered being of this shape. 
