ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 229 



weeds thrown up on the shore, those which can be cut in situ at low 

 water, and those collected from a boat in deeper water. The rights of 

 the French people along the shore, who use the wrack for agricultural 

 purposes and for fuel, are carefully defined. Also an account is given 

 of the progress of the industry in the United States. In the second 

 chapter the author discusses in detail the application of wrack to agri- 

 cultural purposes in various countries. It promotes the growth of 

 excellent potatoes and barley, and has been of great use in checking the 

 ravages of Phylloxera in vineyards. Among its advantages is its freedom 

 from noxious insects, seeds, etc., which are common in ordinary farm- 

 yard manure. He discusses the chemical value of the giant Laminari^e 

 harvested in the Pacific, quoting various analyses, and refers to the 

 methods of drying, etc., which is .carried out on a large scale and with 

 great success. The third chapter deals with the industrial utilization 

 of the Brown alg^e, and describes the commercial uses to which they 

 have been put to in old days ; the processes of calcination and lixivia- 

 tibn ; the extraction of soda, potash, iodine ; algin and its properties ; 

 algulose and alga^-paper ; norgine ; process of fermentation ; sugars ; 

 pectic compounds (algin, fucin, fucoidin) ; intracellular substances 

 (mannite, fucosan, laminarin) ; and, finally, the use of Zostera and 

 Posidonia in the making of paper. In the fourth chapter the author 

 discusses the industrial-utilization of the Red algye under the headings : 

 iodine ; mucilaginous and gelatinizing properties ; fabrication of funori 

 and kanten in Japan ; carra'gheen, its collection, properties and uses ; 

 chemical nature of the mucilages. Chapter Y. contains an account of 

 the utilization of marine algte for food of man and of animals (experi- 

 ments in feeding French horses during the AVar), with an interesting 

 account of marine herbivores, the blue diatom and the green coloration 

 of oysters. The sixth and final chapter describes various uses of marine 

 alg£e and their culture ; the use of dried stipes of Laminari^e ; of algse 

 for fishing line, and as bait for certain fishes ; red alga3 and Tyrean 

 purple ; medical use of certain alg^ ; preparation of algfe for herbaria, 

 etc. ; and culture of marine alges in Great Britain and Japan. The 

 work of Lefranc is cited as showing that Tyrean purple is the product 

 of two gastropods and not of algae. A bibliography, a table of authors' 

 names, an index, and a synopsis complete this interesting work. 



E. S. G. 



Feeding of Horses with Marine Algse.— C. Sauvageau and L. 

 MoREAU {C.R, Acad. Sci. Paris, 1919, 168, 1257-61). Describes the 

 experiments made in 1918 in France to make good the scarcity qf 

 forage, especially oats, for horses by feeding them on marine alga}. 

 Horses which had been placed on the sick list were first treated, their 

 oats ration being replaced by alg». They recovered. Healthy horses 

 were then gradually trained to accept the new food, both chemically 

 prepared and in a natural state. The algte employed were Fiicus 

 serratus and Laminaria flexicaulis. The results were excellent, and the 

 horses under observation were able to do full work without any ration of 

 oats. L. saccharina, however, was obstinately refused. This fact had been 

 noted by former observers, who had recorded the feeding of Norwegian 



