ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 59 



aiid G. sinensis, from Louisiana and China respectively. Another new 

 species is C. Nicholsoni Douin and Schiffn., which is carefully differen- 

 tiated from C. JIassalongi Spruce and C. eeraria Pears. The original 

 specimen of C. Bryhnii Kaal. (non Schiffn.) contains an admixture of 

 C. rubelld (Nees) and of another species now provisionally described and 

 named G. fallax Douin. Under the heading " Quelques melanges 

 embarrasants " Douin discusses the following cases and the characters- 

 by which the species may be discriminated : — C. StarJdi and G. Lim- 

 'pricKU ; G. Hampeana and G. rubella ; G. striatula Jens, and G. Starkii ; 

 G. Jackii and G. rubella ; G. elegans and G. Starkii ; G. hifidoides Douin 

 (a new species), G. integerrima (Lindberg), and Dichiton calyculatwn 

 Trev. ; G. Starkii and G. papiUosa Douin ; G. Starkii, G. rubella, G. 

 pulcheUa and G. Limprichti. For the proper determination of the little 

 species of Gephaloziella it is indispensable that the specimens should be- 

 complete, with fruit, and in good condition. In the plate are figured 

 many details of the structure of G. myriantha Lindberg, G. Nicholsoni 

 Douin and Schiffn., and G. JIassalongi Spruce. A. G. 



Sphagna, their Habitats, Adaptations and Associates. — W. 

 AYatson {Annals of Botany, 1918, 32, 535-51, 5 figs.). A study of 

 the Sphagna of Somerset, their distribution, protective devices, reasons- 

 for protective devices, further characters important in relation to water- 

 supply. The Sphagna obtain their mineral salts from very dilute 

 solutions. They possess a special method of obtaining mineral food 

 by absorbing the base and liberating the acid. In order to do this, special 

 devices (which may seem of a xerophytic nature) are adopted to obtain 

 a sufficient quantity of dilute solution, and to get rid of the superfluous- 

 acid and water. These devices vary in different groups of Sphagnum. 

 During periods of drought the income of exposed plants is suspended 

 and the xerophytic devices may act as such, keeping the plant in a moist 

 condition till a further supply of dilute solution is available. Structural 

 details are shown in the figures. A. G. 



'&' 



Cell-Structure and Autospore Formation in Tetraedron minimum 

 — GiLBEET Morgan Smith {Annals of Botany, 1918, 32, 459-64,. 

 1 pi.). An account of the cytological structure of this green alga- 

 Young cells of Tetraedron minimum contain a single nucleus and 

 pyrenoid. Repeated simultaneous karyokineses may produce as many as- 

 eight nuclei within a single cell. Autospores are formed by progressive 

 cleavage, the number of nuclei increasing during the process. Four,, 

 eight, sixteen or thirty-two uninucleate protoplasts are the final product 

 of this cleavage, these protoplasts being metamorphosed over into auto- 

 spores. The pyrenoid disappears after the first cleavage, new pyrenoids 

 being formed de novo in the young autospores. A. G. 



Studies on Schistostega osmundacea. — Y. Toda (Journ. Goll. Sci^ 

 Tmper. Univ. Tohjo, 1918, 40, art. 5, 30 pp., 2 pis., 2 figs.). An account, 

 of the occurrence of Schistostega in Japan, its relation to light, heat and 

 humidity, with figures of the structure of the protenema under various, 

 conditions. 1. The optimum intensity of light for thi« so-called- 



