98 



THE GYPSY MOTH APPENDIX. 



from the dish was evaporated to a convenient volume upon a 

 water bath, when aliquot parts of the liquid were taken for 

 the determination of phosphoric acid and potash. The phos- 

 phoric acid was determined by the ammonium molybdate 

 method and the amount of potash estimated as the double 

 chloride of platinum, following as closely as possible the 

 methods of fertilizer analyses adopted in 1895 b}^ the Asso- 

 ciation of Official Agricultural Chemists. Briefly stated, the 

 results of these analyses were as follows : 



Phosphoric acid found in 66 larvae, . 

 Potash (K. 2 O) found in 66 larvse, 

 The phosphoric acid as above stated, 

 in the form of tri-potassic phos- 

 phate, requires of potash, 



Error, 



Grams. 



.036998, 

 .073750, 



.073450 



.000300 



per larva, 

 per larva, 



Milligrams. 



.560 

 1.117 



This shows conclusively that the phosphoric acid and 

 potash in the alimentary canal of this insect exist in the form 

 of tri-potassic phosphate, K 3 PO 4 . 



STUDIES ON OTHER LEPIDOPTERA. 



To learn how commonly phosphate of potash occurs in the 

 alimentary canal of Lepidoptera, a number of larva} were 

 dissected and the parts removed for analysis. The following 

 table presents the results of the analyses. Unless otherwise 

 stated, the data pertain to the alimentary canal of the larva 

 of the species mentioned. 



