442 SUMMAKY OF CUKKENT RESEAECHES EELATIXG TO 



Hepaticae : — Phytophysa Treubii on a species of Pilea ; Anabsena Cyca- 

 dearum on the roots of various Cycadeae ; Nostoc lichenoides on species of 

 Anthoceros and Blasia, &c. 



Carbohydrate of Carrageen-moss.* — J. Sebor has determined the 

 nourishing constituent of Cltondrus crispus to be a complicated carbo- 

 hydrate composed of galactose, glucose, and fructose, together with a 

 small quantity of pentoses. 



Swarmspore Formation in Hydrodictyon. f — According to H. G. 

 Timberlake, the best medium for cultivating Hydrodictyon reticulatum 

 and inducing the formation of swarmspores is a mixture of 100 cc. 1 p.c. 

 aqueous solution of iridium chloride and 3 cc. glacial acetic acid. There 

 is no differentiated chromatophore in the cell. The pyrenoids and nuclei 

 are scattered irregularly throughout the cytoplasm, and the chlorophyll 

 is contained in the whole cytoplasmic body. The nuclei in both the 

 resting and dividing stages show the structure typical of higher plants. 

 Cleavage takes place by means of surface constriction of the protoplasmic 

 membrane on the outside and the vacuole membrane on the inside of 

 the protoplasmic layer. The process is a progressive one, the cleavage 

 furrows cutting out tirst large irregular multinucleated masses of 

 protoplasm, which are in turn broken up into smaller masses, until each 

 contains a single nucleus, the entire protoplast being thus broken up 

 into spores. The swarmspores are uninucleated biciliated cells. At 

 the base of each pair of cilia is a clearly defined basal body. 



Fungi. 



Germination of Fungus-Spores4 — A series of experiments made by 

 B. M. Duggar on about twenty species of Fungi — especially Aspergillus 

 Jiavus and Sterigmatocystis niger — furnish fresh evidence of the extent to 

 which the germination of spores is affected by chemical and physical 

 agents. Salts of potassium and magnesium are not, as has been stated, 

 absolutely indispensable for the germination of all the lower Fungi. On 

 the other hand, germination is often favourably influenced by substances 

 which yield no nutriment. Changes in the form of the hanging drop 

 and in the rapidity of evaporation may accelerate or retard germination. 

 Small differences in the temperature aud in the supply of oxygen pro- 

 duced but little result. The length of time during which spores 

 retained their power of germination varies greatly with different species, 

 — only 24- hours with Botrytis vulgaris, 65 days with Aspergillus flavus. 



Sources of Nitrogen for Fungi.§ — Mary H. Smith finds pepton to 

 be a favourable source of nitrogen for saprophytic fungi (Aspergillus 

 Jiavus, Botrytis vulgaris). In potassium nitrate and potassium nitrite 

 both fungi grew luxuriantly, the Aspergillus developing well-formed 

 fructification. 



New Genera of Fungi. — Parasitic on the leaves of a Lorantlius in 

 Brazil, P. Hennings || finds a fungus which he makes the type of a new 

 genus Pilgeriella, allied to Trichosphseria : — Perithecia membranacea, in 



* Oesterr. Chem. Ztg., iii. (1900) p. 441. See Bot. Centralbl., lxxxvi. (1901) p. 70. 

 t Bot. Gazette, xxsi. (1901) p. 203. $ Tom. cit.. pp. 38-66. 



§ Tom. cit., pp. 126-7. || Hedwigia, xxxix. (1900) Beibl., p. 134. 



