26 



SCIENCE 



[N. S. Vol. XXVII. No. ( 



elected chairman. Nineteen persons were 

 present. 



Mr. G. V. Nash exhibited a flowering speci- 

 men of the orchid MasdevalUa hella. The Eev. 

 Leander T. Chamberlain read an extract copied 

 from the Province Laws of Massachusetts, 

 1736-1761, p. 153, entitled "An Act to Pre- 

 vent Damage to English Grain, arising from 

 Barberry Bushes." All persons in the prov- 

 ince having barberry bushes growing on their 

 land, were ordered to destroy them before a 

 named date. Severe penalties were prescribed 

 on failure to comply with this law. A brief 

 discussion of the subject followed. 



Dr. Britton exhibited a specimen from 

 Jaraaica, W. I., illustrating an economic use 

 of cat-tails. This was a " bed," made from 

 the split stems of the Typha doming en^is. 



The following scientific program was pre- 

 sented : 



A New Utricularia from Long Island: John 



Hendley Barnhart. 



The new species was described and speci- 

 mens of it exhibited. The paper and de- 

 scription will be published in full in the Bul- 

 letin of the Torrey Botanical Club, for De- 

 cember, 1907. 



Borne Anomalous Leaf-forms: C. Stuaet 



Gager. 



Specimens were shown illustrating the 

 formation of ascidia in the white ( ?) clover 

 and in a leaflet of the licorice (Glycyrrhiza) ; 

 variations in the branching of the leaf-blade 

 of a species of Fraxinus; transitions, in 

 Aralia racemosa, from a once-compound to a 

 normally twice-com'pound leaf; branching of 

 the leaflets of Hicoria ovata and of ^sculus 

 hippocastanum; and various stages of transi- 

 tion, in 'Gleditschia triacanthu^, from once- 

 compound leaves to twice- and thrice-com- 

 pound ones, the transitional forms occurring 

 in some instances on the same branch, and 

 even on the same leaf. Eosette leaves were 

 also shown from several species of Biotian 

 asters, showing gradual transitions from a 

 slight indentation of the margin of the blade 

 along its basal half to the development of 

 petiolate leaflets, so that the leaf appeared to 

 be a pinnately compound one. The possible 



causes of these variations were briefly dis- 

 cussed. 



Brief discussion followed the presentation 

 of both papers. 



C. Stuart Gager, 



Secretary 



THE AMERICAN CHEMICAL SOCIETY. NEW YORK 

 SECTION 



The third regular meeting of the session of 

 1907-8 was held at the Chemists' Club, 108 

 West 55th Street, on December 6. 



Messrs. T. J. Parker, L. H. Baekeland, Hugo 

 Schweitzer, G. C. Stone, E. G. Love and 

 Morris Loeb were elected to represent the sec- 

 tion in the council of the society. 



The following papers were read: 



The Relative Solubility of Silver Halides and 

 Silver Sulphocyanate : Arthur E. Hill. 

 The solubilities of silver chloride, sulpho- 

 cyanate, bromide and iodide are compared by 

 the method of solution equilibrium; when 

 silver chloride, for example, is treated with a 

 solution of potassium sulphocyanate a partial 

 decomposition of the chloride occurs, as shown 

 by the expression 



AgCl -h KCNS ?± AgCNS -f KCl . 

 According to theory, 



where ^S'^ and S^ stand for the solubilities of 

 the two difiicultly soluble salts, expressed in 

 equivalents per liter, and 0^ and 0„ are the 

 concentrations of their anions in solution 

 when equilibrium has been reached. The salts 

 considered are well suited to study by this 

 method, since the dissociation constants of the 

 potassium salts are equal, and the silver salts 

 are all totally dissociated ; hence no corrections 

 for inequalities in dissociation are necessary. 

 By application of the foregoing formula to 

 the four salts mentioned, in solutions of vary- 

 ing concentration, the relative solubilities at 

 25° C. are found to be as follows : 



AgCl = 1.00000 

 AgCNS = 0.07480 

 AgBr =0.05500 

 Agl = 0.00077 



