826 EXPERIMENT STATION RECORD, 



The probable function of calcium oxalate crystals in plants, A. Schneider 

 {Bot. Gaz., 32 (1901), No. 2, pp. 142-144) ■—GaXcmm oxalate is said to occur in plants 

 in 4 predominating types. Of these the least common is that called crystal sand. 

 The prismatic^ and aggregate forms are about equally common and are very widely 

 distributed. The needle-shaped or acicular crystals are very common but predomi- 

 nate in monocotyledonous plants. The author reviews the common opinion that 

 calcium oxalate occurs in plants as a protective agent, and from his own and other 

 observations concludes that its prime function is that of mechanical support, and that 

 its role as a reserve product is dou]>tless secondary. The principal reasons favoring 

 the mechanical support theory are given at some length. Cells containing prismatic 

 crystals are generally associated with bast fibers. As a rule the crystal-bearing cells 

 are thin-walled and each contains a single crystal. These cells surround the bast 

 fibers or bast bundles, and are very abundant in the bark of manj' trees. In other 

 instances the crystal -bearing cells are believed to serve as a substitute for mechanical 

 tissues, taking the place of sclerenchyma. For example, in the seed of the quince 

 and the ordinarv garden bean, particularly in the latter, the sclerenchymatous ti.ssue 

 is replaced by a layer of cells containing large prismatic crystals so constructed and 

 placed as to 1)est resist vertical and lateral pressure. In the case of the acicular crys- 

 tals of monocotyledonous plants it is quite evident that they give elasticity as well 

 as support against pressure. The crystoliths which occur so abundantly in Ficus 

 leaves perform a purely mechanical function. It is frequently found that cells bear- 

 ing calcium oxalate take the place of mechanical cells in leaves, which is particularly 

 true about the stomata of the leaves. It is believed to be highly probable that in 

 many plants and plant organs calcium oxalate exi.sts accidentally, but in the major- 

 ity of instances its function is that of mechanical sujijiort, as indicated. 



The sensitiveness of higher plants to the action of salts of potash, 

 H. CouPiN {Compt. Rend. Acad. Sri. Parift, 132 {1901), Xo. 25, pp. 15S2-U,84).—ln a 

 previous paper (E. S. R,., 13, p. 620) the author has shown the remarkable sensitive- 

 ness of some plants to very small quantities of toxic sul)stances. The present paper 

 reports the sensitiveness of plants to some of the useful salts. Experiments were 

 made with wheat which had been germinated. After unfolding the second leaf the 

 seedlings were placed in solutions containing known quantities of potash salts, and 

 comparisons made with the development of plants in distilled water. The strength of 

 the stronger solution was 1 :5,000, and this was decreased in a regular arithmetical pro- 

 gression through a series of 13 cultures. It was found that the i>lants were sensitive 

 as shown by their growth to various salts of potash as follows: Potassium carbonate, 

 1:1,000,000; potassium phosphate, 1:25,000,000; potassium sulphate, 1:8,000,000; 

 potassium chlorate, 1:.'>00,000; and potassium nitrate, 1:400,000. These figures show 

 the remarkable sensitiveness of the plants to the action of potash salts. 



The etherizing- of plants, E. Ch.vrabot and A. Hebert [Compl. Rend. Acad. 

 >Sci. P(iri.% 133 {1901), Xo. S, j)p. 390, 391). — It is claimed that terpene alcohols are 

 transformed into ethers in the chlorophyll-bearing organs of plants, and that the 

 etherizing is most active when the jilant is be.st adapte<l for assimilation. The 

 etherization in the plants is produced l)y direct action of acids on alcohol, and it is 

 favored by the presence of diastase, which exerts a dehydrating action through the 

 medium of the chlorophyll. 



Notes for a monograph of the phenomena of plant transpiration, A. Bur- 

 GERSTEiN {Vi'rhandl. K. K. Znol. Bot. Gei<ell. Wifu, r,l {1901), Xoa. 1, pp. 49-64; 2, 

 pp. 65-106; nbs. in Bot. Centhl., 87 {1901), No. 7, jyp. 233, 234).— The methods of 

 investigation are given and descriptions of intercellular and epidermal transpiration; 

 transpiration of leaves and of the palisade parenchyma; the transpiration of halo- 

 phytes and succulent plants; the influence of light, temperature, moisture, and 

 antesthetics upon transpiration; transpiration and the phenomena of transpiration 

 exhibited by tropical plants, and other special variations. 



