MICROSCOPIC OBJECTS. 10 



Fig. 19. Liber-tissue from Jute (Corchorus capsularis), 



x 200. 



Liber-cells or -tissue constitute a form of prosenchymatous 

 tissue consisting of elongated cells tapering to a point at 

 each end. These are often united into bundles, as in Hemp, 

 Jute, &c. 



When liber-fibres are treated with acids, their individual 

 appearance is considerably altered, although in their ordinary 

 condition they do not appear to differ ; but they may always 

 be distinguished from Cotton and other vegetable hairs by 

 their structure. 



Most liber-cells appear to have rather a dense thickening 

 of the secondary deposit. 



This tissue is best mounted in liquid ; but if required for 

 the polariscope, in Canada balsam. 



Fig. 20. Laticiferous Tissue from the Celandine (Chelidonium 

 majus), x 120. 



This tubular kind of structure pervades the tissues of the 

 Papaveracese, Euphorbiacese, &c., and may generally be distin- 

 guished from the surrounding structures by its peculiar 

 branched appearance, although in some cases it is nearly 

 simple and straight. The canals convey a kind of milky 

 juice, called latex, and they are generally regarded by scien- 

 tific authorities as being in some degree a part of the system 

 of vessels that contribute to the circulation of plants. The 

 canals seem to thicken in their coats by the deposition of the 

 latex. The common Celandine is one of the most handy 

 plants in which to observe this tissue. 



It is best mounted in weak spirit and water. It may be 

 extracted by maceration in water, and subsequent dissection. 



