312 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Protophyta. 

 o. Schizophycese. 



Polycystic* — W. Zopf has extracted the pigment from the floating 

 " water-bloom," Polycystis flos-aquse, belonging to the Cyanophyceae, 

 and finds it to be of the nature of a carotin, but distinct from any yet 

 described. It can be obtained pure in several distinct crystalline forms. 

 Its spectroscopic and other properties are described in detail. 



Chlorogloea, a New Genus of Cyanophyceae.f — Prof. N. Wille has 

 determined Hansgirg's Palmella (?) tuberculosa from the Adriatic (now 

 found on algae and shells in Christiania fiord) not to be a green alga at 

 all, but to be the type of a new genus of Chauiaesiphonaceae, Chlorogloea, 

 with the following diagnosis. Colony irregular, consisting of a number 

 of round or oval cells, which divide in one direction only and form 

 radiating rows of cells, surrounded by a thin unstratified mucilaginous 

 envelope. Cells without a nucleus, but with a slightly differentiated 

 parietal yellowish or verdigris-green chromatophore ; propagation by 

 division only ; new colonies formed by the setting free of akinetes by 

 the gelification of the mucilaginous envelope. Epiphytic on algse or 

 epizootic on Bryozoa in salt water. 



£. Schizomycetes. 



Myxobacteria.J — Miss A. Lorrain Smith has found on rabbit's dung 

 a new species of Myxobacteria to which she gives the name Myxococcus 

 pyriformis sp. n. The cysts are of a bright pinkish orange colour. 



Effect of Physical Agents on Bacterial Life.§ — Dr. A. Macfadyen, 

 in a discourse delivered at the Royal Institution, described the effect of 

 physical agents on bacterial life. The action of desiccation, and of sun- 

 light in preseuce and absence of oxygen, the effect of mechanical agita- 

 tion, of pressure, moisture, high and low temperatures, were the chief 

 points alluded to. Special attention was given to the effect of raised 

 temperatures and the useful results of pasteurising milk, the lecture con- 

 cluding with references to the influence of very low temperatures on 

 bacterial life. 



Insects as Factors in the Spread of Bacterial Diseases.|| — S. Burrage 

 caused flies previously infected with typhoid and prodigiosus to walk 

 over the surface of Petri plates. The plates developed colonies of the 

 organisms, from which it is evident that the fly can become infected with 

 bacterial filth, and hold on to it for sufficient time to inoculate food 

 materials. 



Influence of Ozone on some Pathogenic and other Bacteria.! 

 — Dr. A. liausome and A. Gr. K. Foulerton find that ozone in the dry 

 state has no appreciable action on the vitality of the various bacteria ex- 

 perimented with ; nor did a prolonged exposure to the action of ozone 



* Ber. Deutsch. Bot. Ges., xviii. (1901) pp. 461-7 (1 pi. and 1 fig.), 

 t Algol. Notizen, i.-vi., in Nyt Mag. Naturvid., xxxviii. (1900) pp. 1-27 (1 pi.). 

 See Bot. Centralbl., lxxxv. (1901) p. 129. 



X Journ. of Bot., xxxix. (1901) pp. 69-72 (3 figs.). 



§ Nature, lxiii. (1901) pp. 359-|j2. 



|| Proc. Indiana Acad. Sci., 1899 (1900) pp. 68-75 (5 figs.) 



i[ Froc. Row Boc, lxviii. (1901) pp. 55-64. 



