252 
KBYTE WS. 
The Coagulation off Latex. 
By J. PAEKIN 
(Indiarubber World, New York, 1901.) 
A REPLY to criticisms by Mr. J. H. Hart of Trinidad. 
J. C. W. 
A Simple Test for Thein. 
By a NESTLER. 
(Ein einfaches Verfahren des Nachweises von Thein, und seine 
praktische Anwendung. Zeitschr. für Unt. d. Nahrungs-und 
Genussmittel, lY., 1901, p. 289.) 
A PORTION of the leaf to be tested is powdered, placed in a watch- 
glass, covered with another of the same size inverted, and heated over 
a small Bunsen flame or spirit lamp. In a few minutes drops appear 
on the upper glass and soon crystals form, especially if a drop of 
water be placed on the top of the glass. These are crystals of thein ; 
they may be tested by Molisch’s method, by treatment with concen- 
trated hydrochloric acid and subsequent addition of a 3 per cent, 
solution of chloride of gold, when long or short yellowish crystals al 
once form in bundles. 
J. C. W. 
A Monograph off Niphobolus. 
By K. GIESENHAGEN. 
(Die Farngattung Niphobolus ; Jena, 1901 ; pp. 226, Mk. 5*50.) 
A VERY full anatomical and systematic monograph of this old world 
group of ferns. Dr. Giesenhagen spent some time at this work at 
Peradeniya, and the results of his examination of our living and dried 
material are included. The Ceylon forms are redistributed to some 
extent, and a new species, N. ceylanicus^ Giesn., is described on p. 216 ; 
this was found in the herbarium of Prof. Christ» at Basel, collected 
by G. Wall, No. 48/278, as N. adnascens^ Sw. 
J. C. W. 
The Bacterial Warts on the Leaves off Pavetta 
indica and other Rubiaceæ. 
By a. ZIMMERMANN. 
(Ueber Bakterienknoten in den Blättern einiger Rubiaceen. 
Jahrb. Wiss. Bot., 37, 1901, p. 1.) 
The leaves of several species of Pavetta, e.g.^ P. indica (Pawatta. 
Sin.), have curious warts most prominent on the upper surface. 
These are found to be due to the presence of bacterial colonies in the 
leaf. The meaning of this phenomenon is to be the subject of further 
investigation. 
J. G, W. 
