208° Prof. G. Gulliver on the Fibrin and Latex of Vegetables, 
I have seen this fibrin in the clear juice of many fleshy roots ; 
but on the present occasion it will be described from observa- 
tions on the latex, and from my notes of experiments on that 
of numerous species of the orders Papaveracee, Campanulacee, 
Composite, Convolvulaceze, and Urticacez. These are only 
mentioned as examples; for the facts to be described may be 
witnessed in other orders. 
If the latex be let out of the plant, it will commonly coagulate 
quickly,—in Jess than four minutes, if in very small quantity, 
as may be seen in a drop, or less, on a slip of glass. In large 
quantities, as of several drachms, coagulation may or may not be 
slower. And that this coagulation is owing to the fibrin, pre- 
viously a colourless and limpid fluid, may be easily shown, both 
during and after its coagulation. The coagulable property is 
probably affected by season and temperature; for the juice of 
the very same plant, which will soon coagulate spontaneously in 
summer, frequently requires more time or fails altogether to do so 
in February and the cold months. The clot is often structureless, 
and sometimes composed of an intimate texture of fibrils. I 
have seen them closely resembling those of animal fibrin, long 
since depicted by me (App. to Gerber’s ‘Anatomy,’ figs. 244-246 ; 
and Phil. Mag. for Aug. & Sept. 1842), but less closely packed, 
and so forming a looser tissue, such as we are familiar with in 
dilute or weak forms of human fibrin. 
But this vegetable fluid differs remarkably from liquor san- 
guinis in being often coagulable by water. So rapid or instan- 
taneous may the effect of water on the plant-fluid be, as to 
remind one of the action of corrosive sublimate on albumen 
generally, and of water on the albuminous substance of the ova 
of fishes particularly. 
The colour and opacity of the latex, whether white or yellow, 
is generally due to particles of extreme minuteness, about z5455 
English inch in diameter. These are very equal in size, form 
the base of the juice, and altogether closely resemble the mole- 
cular base of the chyle of Mammalia, as originally described and 
figured in my Appendix to Gerber’s ‘Anatomy.’ This molecular 
base, with certain exceptions presently to be noticed, is the 
whole opake matter visible in the vegetable latex; and the 
limpid fluid containing the fibrin and this molecular base are 
quite different parts. These parts might be respectively distin- 
guished as the molecular base and liquor laticis. 
But the milkiness or opacity of the latex of some plants, as in 
certain Convolvulacese, Cynarocephale, and Urticacez, is not 
owing to this molecular base, but to larger oil-like globules, of 
very unequal size and distinct outline. In Convolvulus, these 
globules vary from 34455 to 5,55 inch; in the garden Fig they 
