Prof. H. Mohl on the Latex and its Movements. 441 



XLIX. — Researches on the Latex and its Movements. 

 By Prof. H. Mohl*. 



The author comments upon the variety of opinions that have 

 been entertained concerning the latex, and considering the great 

 importance of the subject in relation to vegetable physiology, and 

 the entire incompatibility of M. Schultz's theory with all previous 

 notions, he felt that it was necessary to make a careful examina- 

 tion of the facts on which that author had founded his theory. 

 In the present paper he refers only to the last two works of 

 Schultz, ' Memoire sur la circulation et sm' les vaisseaux latici- 

 feres dans les plantes,' a prize essay which was crowned by the 

 Paris Academy of Sciences in 1839 ; and ' Ueber die Cyklose des 

 Lebenssaftes ^ in the ' Nova Acta Acad. Nat. Curiosorum,^ 1841. 

 He intimates that he shall probably consider the anatomical rela- 

 tions of the laticiferous vessels on a future occasion. 



1. Organization of the Latex. 



According toM. Schultz, the milky juices consist of a coagulable 

 liquid in which float a number of globules. The globules are 

 chiefly composed of fatty or waxy matters ; the small globules of 

 wax, and the larger of membranous sacs inclosing fatty substance. 

 The liquid (plasma) coagulates when exposed to the air, a sub- 

 stance which he calls elatine (chiefly composed of caoutchouc), 

 separating from it as fibrine does from coagulating blood. The 

 globules do not participate in the coagulation ; they present true 

 vesicles containing a nucleus, and do not entirely dissolve in al- 

 cohol or sether, but shrivel up, and the fatty substance is then 

 dissolved out. 



Prof. Mohl states that he has obtained results which make 

 M. Schultz's theory of the organization of the latex appear 

 erroneous. 



By placing a small quantity of latex between two slips of glass 

 and sKding these over one another, it may easily be seen that the 

 globules are composed of a softish, very viscid matter, that press- 

 ure unites them, and that there is no trace of an enveloping 

 membrane ; they may be collected and di'awn out in a stringy 

 mass, beneath the microscope, with the point of a fine needle. 

 When a thin layer of latex is dried on glass, the liquid in which 

 the globules float is changed into a transparent crust, which may 

 be dissolved in water so as to re-establish the original condition 

 of the sap. This di'ied serum forms a brittle mass, which, like 

 a thin layer of gum, breaks with shai-p angles, while the globules 



* From the Botanische Zeitung, 1843, p. 553. 



We are indebted to the kindness of Mr. Henfrey for the communication 

 of this abstract. — Eds. 



Ann. ^ Mag. N. Hist. Vol. xiii. 2 G 



