578 ABSTRACTS 



Studies on the Crown Gall of Plants: Its Relation to Human Cancer. 



Erwin F. Smith. (Journal of Cancer Research, 1916, I, 231-258, 



87 pi.) 



The author reviews first the geographical and botanical distribution 

 of crown gall. This disease is differentiated from hypertrophic en- 

 largements in plants due to a few special parasitized cells as in the root 

 nodules of legumes and slime mold infections in crucifers, as well as 

 from granulomatous hyperplasia such as those of the olive tubercle 

 where the bacteria are imbedded between the cells. Crown gall is a 

 peculiar hyperplasia caused by Bacterium tumefaciens developing 

 sparingly and only intracellularly, the parasitized cells being thereby 

 caused to divide prematurely and repeatedly, which results in a great 

 mass of non-capsulated small celled tumor tissue in which the bacteria 

 themselves are invisible. 



The tumor resembles cancer in many ways, notably in the exhibition 

 of growth independently of function, vegetative activity being stimulated, 

 functional activity depressed. The tumor can be stimulated by feed- 

 ing or starved into quiescence. It can be grafted upon other plants of 

 the same species. As in mammalian cancer, the nuclei of the tumor 

 divide both mitotically and amitotically. Due to the rigid cell walls 

 of plants, on the other hand, true metastasis seems not to occur. 



The writer mentions especially the atypical arrangement of the tis- 

 sues, their loss of polarity and the anaplasia, or undifferentiation of 

 the cells. The production of tumors varying in structure according to 

 the type of tissue experimentally invaded, among which were recog- 

 nized embryonic organ inclusions analogous to the teratomata of mam- 

 mals, is recorded for the first time. 



The bacteriology of the parasite is discussed briefly, as are also some 

 experiments with animals. — I. C. H. 



PUBLIC HEALTH BACTERIOLOGY 



Public Health Laboratories. R. G. Perkins. (New York Med. Jour., 



1916, 103, 721-724.) 



A discussion of the activities of public health laboratories. Among 

 the suggestions made for furthering the development of these labora- 

 tories it is particularly recommended that there should be close asso- 

 ciation between the laboratory and a high grade university, in order 

 that conditions should be made ideal for research work. — Mj W. C. 



The Microscopic Examination of Finger Nail Deposits. S. Schneider. 



(Jour. A. M. A., 1916. 66, 1615-1617.) 



The microscopic examination of finger nail deposits reveals the fact 

 that the usual methods of cleansing the hands and nails does not result 

 to any considerable degree in removing deposits. 



Bacteriologic examination of deposits shows microorganisms to pre- 

 dominate in the following order: streptococci; staphylococci; Bacillus 

 coli; bacilli, cocci, and spirillae derived from diverse sources; yeast 



