DEC .6 1996 Pho ee eA GE TONS 
DEbdLrS eta 
AMERICAN PHILOSOPHICAL SOCIETY, 
HELD AT PHILADELPHIA, 
FOR PROMOTING USEFUL KNOWLEDGE. 
VOLUME XIX —NEW SERIES. 
PAR bak 
Fi 
ArvicheE I.—A New Method of Determining the General Perturbations of the Minor Planets. By 
Wiliam McKnight Ritter, M.A. 
ARTICLE II.—An Hssay on the Development of the Mouth Paris of Certain Insects. By John B, 
Smith, Sc.D. 
Hhiladelphin: 
PUBLISHED BY THE SOCIETY, 
AND FOR SALE BY 
Tue American PuHinosopHicaLt Society, PHmapELPHIA 
N. TRUBNER & CO., 57 and 59 LUDGATE HILL, LONDON. 
1896. 
