BULLETIN OP THE UNITED STATES FISH COMMISSION. 453 



The difi'erence between the practical value and the price is therefore 

 very small, and the expense can be still further reduced if a portion of 

 the ground meat is replaced by cockchafers and a portioin of the oats 

 by cheap Hour. 



3ir.— ON MANUFACTrRED FOOD FOR TROUT AIV1> CARP.* 



By CARL NICKLAS. 



There has lately been published an article by Prof. G. O. Harz, giving 

 the results of his microscopic examination of my food for trout and carp 

 manufactured by Louis Goos, of Heidelberg. These results astonished 

 me, for Dr. Harz has found in this food, with the exception of ground 

 meat, all sorts of ingredients except those of which it is composed. The 

 following sentence is characteristic of the entire examination: " I was 

 not able to arrive at any definite results as to the ijresence or absence 

 of linseed." 



In order to be absolutely certain that Goos had manufactured the food 

 in strict accordance with my receipt, I informed him of Dr. Harz's ex- 

 amination, requesting him to have the food, which had already been 

 chemicidly examined at Marburg, also analyzed microscopically. I 

 give below the result of this analysis : 



Maebukg, May 9, 1884. 

 Mr. Louis Goos, Heidelberg : 



The specimen, of fish -food transmitted November 3, 1883, by the As- 

 sociation for Furthering Fish-culture in the district of Kassel (Mr. 

 Georg Seelig, in Kassel), when examined March 25, 1884, was found to 

 contain — 



Per cent. 



Water 13.34 



Proteiue substances 46. 75 



Fat 10.50 



Hydrate of carbon -. 16.87 



Wood- fiber 1.60 



Mineral substances 10.83 



This fish-food, according to the microscopical examination, is mainly 

 a mixture of ground meat (meat-flour), an article of food which at pres- 

 ent is used very extensively in agriculture, and flour i)repared from the 

 fruits of leguminous plants (probably vetches) ; its ingredients are, 

 therefore, highly nutritive. "Wheat and oats occur in small quantities, 

 and indeterminable substances in exceedingly insignificant quantities. 



Prof. Dr. DIETRICH, 

 Director of the Experimental Agricultural Station. 



« II 



Ein Fischfutter fur Fordlen und Karjyfcn." From tbo DeuUche Fischei-ei-Zeitung, 

 vol. vii, No. 23; Stettin, June 3, 1884, Translated from the German by Herman 

 Jacobsox. 



