42 THE TISSUES OF PLANTS 
(m) For the study of laticiferous tissue thin tangential 
sections are best. The tissues will show as tubes filled with a 
brown granular mass, the latex. The non-anastomosing type 
can be found in the milkweed (Asclepias), dogbane (Apo- 
cynum), and spurge (Euphorbia), especially the more fleshy 
forms of the latter. The anastomosing type can be studied 
in the petioles of dandelion or lettuce, or in the stem of the 
poppy. 
(n) The long, branching, non-anastomosing laticiferous tubes 
of Euphorbia can be isolated from the more fleshy leaved sorts 
by boiling the leaves in dilute potash solution and then toneing 
out a piece of the softened tissues. 
(0) To examine the tissues in situ, the leaves should be 
placed in strong alcohol (90-95%) for some hours. If the 
leaves are thick, thin sections should be made parallel to 
the surface. These sections, or the whole leaves if they are 
thin, should then be placed for an hour or so in a clearing fluid 
made of equal parts of turpentine and carbolic acid (phenol). 
Mount the section or leaf in this fluid. The tissues are made 
transparent, and the laticiferous tubes filled with granules of 
latex can be studied with great ease. The same method can be 
used for studying both types of laticiferous tissue. 
REFERENCE BOOKS 
The books enumerated for Chapter I and the following. 
A. DeBary, Comparative Anatomy of the Vegetative Organs of 
Phanerogams and Ferns (Engl. Ed. 1884. Oxford). 
G. Haperutanpt, Physiologische Pflanzenanatomie, Leipzig, 
1904. (Engl. Ed. 1914. London.) 
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