2 1 2 S ARCOS PORIDI A. 



disease. Professor Hedinger, in his report, states that the 

 clinical investigations point to a connection between grass and 

 lamziekte, and this point can easily be explained by accepting 

 the theory of a sarcosporidiosis ; and although the biolog>' of 

 the sarcosporid is not sufficiently known, we can accept that the 

 infection enters the host with the food. The infection can be 

 a direct one from the grass, or can occur through an inter- 

 mediate host. 



Finally, McGowan, in his recent report on scrapie in sheep, 

 brings forward circtmistantial evidence which points to the 

 possibility of a congenital infectiousness. 



Biological Chemistry. — Almost all the products of 

 vital activity are compounds, or mixtures of compounds, of the 

 element carbon, and, owing to the property possessed in so 

 marked degree by the atoms of that element of combining with 

 each other, the carbon compounds known at the present day 

 number about 150,000. In these days of specialisation it is no 

 matter for astonishment that so niunerous a class of chemical 

 compoimds should have a branch of chemistry all to themselves, 

 and this branch is known as " organic chemistry," because it is 

 so indissolubly associated with bodies possessing an organised 

 structure. The circle may be drawn even closer, and, when con- 

 fined to the carbon compounds which are the constituents of 

 living matter, whether vegetable or animal, and which are con- 

 cerned in vital processes, is called biological or bio-chemistry. 

 Plimmer's " Practical Physiological Chemistry "' was specially 

 compiled as a handbook mainly for medical students, and has 

 been employed for practical bio-chemical work in connection 

 with University College, London. With a medical school 

 gradually developing in South Africa the appearance of a con- 

 siderably expanded edition of this work* will certainly be wel- 

 comed, especially as in its new form it would be difficult to find 

 its superior as an English text-book in practical biological 

 chemistry. It treats bio-chemistry not only from the side of 

 animal physiology, but also from the botanical side, and by 

 means of marginal asterisks and different styles of type it indi- 

 cates which portions of the book are suitable for advanced 

 courses, and which experiments are within the scope of a pre- 

 liminary course. The practical methods are presented as con- 

 cisely and as clearly as choice of diction and arrangement of 

 type can set them forth, and the book will assuredly prove of 

 considerable value in all laboratories charged with the study or 

 investigation of different phases of bio-chemistry, 



* R. H. A. Plimmer : " Practical Organic and Bio-chemistry," 10 X 6in. 

 pp. xii, 635. London: Longmans, Green & Co., iQrs. 12s. 6d. nett. 



