5^()(>LOGY. 1021 



incubation necessary to give an opinion on tlie pnrity of water. Of the dozen or more 

 media tested, that known as Xahrstoff-agar has advantagt'S over all the otlier media 

 fortinantitative work. In all the tests with this nuHhum, the eountsof l)acteria more 

 nearly ai){)roximate tlie actual bacterial content of the water than i.s the case with 

 any other medium known to the authors. This meilium is said to l)e a pnrealbumo.se 

 made from egg albmnen, and, although somewhat comjtlex in compositifm, is les.s 

 liable to vary than the usual materials used. This is considered a distinct advantage, 

 as it enables bacteriologists to prepare a medium of uniform composition, making the 

 re.sults obtained at different laboratories comparable. 



Bacteria and sewage, F. Clowes {Pwc. Boy. JnM. Great Britain, 10 {1900), II, 

 Xn. 94, pp. :U7-.l.'4, .!'!/■■<■ 9). — A discu.ssion is given of the relation between sewage 

 and bacteria, ami the i)uritication of sewage by the action of mnnerous organisms. 



Bacteria and the disintegration of cement, R. (J. Smith {Pror. Linn. Soc. Neiv 

 South Wales, 26 {1901), pt. 1, pp. 107-117). — A number of authors having reported 

 the disintegration of cement linings of waterworks and reservoirs by the action of 

 bacteria led the author to investigate the subject in connection with the Sydney water 

 supply. The cement above water line was hard, while below the water it was soft 

 and easily broken away. An examination of the sediment showed the presence of a 

 considerable number of bacteria; among them were specimens of Vihrio denitrificans 

 and Micrococcus radiatus. Cultures were made of these organisms and they were 

 grown upon cement blocks without any disintegration being oljserved. As a result 

 of these observations the author believes there is consideral)le room for doul)ting the 

 action of micro-organisms on cement, but thinks that the action is purely chemical, 

 brought aljout by the decomposing and solvent action of the water. 



On the nature of certain oxidizing ferments, J. H. Kastle and A. S. Loeven- 

 HART(.ly/i^r. ('Item. .Tour., 26 {1901), Xo. 6, pp. 53.9-566). — A report is given of extended 

 studies on the oxidizing ferment found in the common potato. As a result of their 

 investigations the authors claim that oxygen is alisolutely essential to the production 

 of the guaiacum-l)luing ferment of the potato. This so-called oxidizing ferment, they 

 believe, is an organic perox id and not a true solul)le ferment. It is believed that the 

 oxidizable substances are oxidized to the peroxid condition by molecular oxygen, and 

 that the peroxids thus formed give up part of their oxygen to other less oxidizable 

 substances present in the cell; in other words, that the process of rendering oxygen 

 active by the living cell is ])robablyl>rought about in essentially the same way as that 

 accomplished by phosphorus, benzaldehj'de, and other oxj'gen carriei-s — that is, as 

 one phase of autooxidation. 



Oxidizing enzyms, C. E. Newton {Indian Gard. and Plant., 9 {1901), Xn. 22; ahs. 

 in Jour. Soc. Cheni. Ind., 21 {1902), No. 3, p. 182). 



Note on the production of casease by a streptothrix parasite, E. BoniN and 

 C. Lenohmaxd {Ann. Inst. Pastenr, 15 {1901), Xo. 4, pp- 279-2SS). — The authors 

 describe a fungus of the form Oospore of Microsporum that when grown in a mdk 

 culture produces an enzym that is able to coagulate the casein like remiet and another 

 enzym that possesses the power to dissolve the coagulated casein like the caseaae of 

 Duclaux. 



ZOOLOGY. 



Destroying gophers and prairie dogs, D. E. Lantz {Kansas State Bd. Agr. Quart, 

 apt. 1902, Mitr. P>1, pp. o.'5-.l.iO, pJ. 1, fiij. 1). — Geomijs bursariu.s is generally dis- 

 tributed in theea-stern part of Kansa.«, while G. lidescens is found chiefly in the west- 

 ern parts of the State. The adoption of the bounty system in destroying these pests 

 is considered ineffective. The use of carbon bisulidiifl and traps in the burrows, and 

 scattering poisonerl baits are recommended for destroying these animals. The j)rairie 

 dog is especially conunon in the western part of the State, where it is estimated that 



