382 EXPEEIMENT STATION RECOED. 



" In carnivorous animals, oil of Chenopodiuni usually, but not always, causes 

 a preliminary rise of tone followed by a steady decline. Rhythuiic contrac- 

 tions may increase in frequency but disappear finally. Recovery may take place 

 when the segments are put into Locke's solution. 



" The reaction to oil of Chenopodium was greater in the ileum than in the 

 duodenum or jejunum, but was most marked in tlie colon. Caffein has no 

 antagonistic effect but may, on the contrary, aid depression of tone caused by 

 oil of Chenopodium. Neither barium chlorid nor pilocarpin has a true antago- 

 nistic effect but may prevent to a small extent depression of tone when added 

 before oil of Chenopodium. Pilocarpin has no action on intestine which has 

 been poisoned by oil of Chenopodium, but barium produces an increase of 

 tone. Nerve ends as well as muscle fiber are attacked by oil of Chenopodium, 

 but the latter is more resistant. Relatively large doses of oil of Chenopodium 

 are required to inhibit peristalsis in intact rabbits by intravenous injection. 

 The presence of substances antagonistic to oil of Chenopodium is offered as an 

 explanation." 



Notes on the factors involved in the germicidal effect of freezing and low 

 temperatures, C. M. Hflliard, Christina Tokossian, and Ruth P. Stone 

 (Science, n. ser., 42 {1915), No. 1091, pp. 770, 771). — Ninety-nine per cent and 

 over of Bacillus coli succumbed to freezing in tap water In three hours, 

 while with B. svblilis the reduction wos not at all uniform, but seldom ex- 

 ceeded 80 per cent. Three strains of B. coli tested showed no appreciable 

 variability in relation to the disinfecting influence of cold and freezing. Inter- 

 mittent freezing had but slightly greater germicidal value than sustained freez- 

 ing for the same period of time. 



Tubes containing the bacteria were frozen and held for three hours for 

 comparison nt api)roxiniately —15" C. and —2°. The colder temperature 

 was considerably more fatal. Tubes kept at ^ O.-'i" use<l as controls in most 

 of the experiments showed marked variation, but seldom showed over 30 per 

 cent to 40 per cent of the bacteria to be killed. 



Cream containing 30 per cent of milk fat afforded a very striking protection 

 to the bacteria when frozen, whether the freezing was continuous or intermit- 

 tent. 



The results letl the authors to infer that the degree of cold, time of freezing, 

 crystallization and external pressure, and the composition of the media in 

 which the freezing occurs all have an influence upon the germicidal potency 

 exhibited l^y cold. 



The macrophages of mammals, H. M. Evans {At)ier. Jour. Physiol., S7 

 (1915), No. 2, pp. 24S-258). — A critical discussion of the subject with references 

 to the literature. 



The facts presented " Justify recognition that the great Baass of mononu- 

 clear cells which we have described constitute a sharply defined cell group 

 or class. The macrophages may now be defined as those mononuclear cells, 

 wherever they may be, lining vascular channels, resident in the connective 

 tissues or entirely free, whose protoplasm constitutes a physical system charac- 

 terized above all by its response to finely particulate matter." 



Annual report of the chief veterinary officer for the year 1913, S. Stock- 

 man (Bd. Agr. and Fisheries [London], Ann. Rpt. Chief Vet. Off.. 191S, pp. i4, 

 figs. 2). — This annual report (E. S. R., 31, p. 177) first discusses the outbreaks 

 of foot-and-mouth disease which occurred in 1913 (pp. 4-7), then hog cholera, 

 swine erysipelas, glanders, anthrax, sheep scab, parasitic mange, tuberculosis, 

 abortion, etc., and gives an account of scrapie (pp. 33-^4), including a history 

 of the disease, animals affected, symptoms, nature of the disease, treatment 

 and prevention, and general suggestions. 



