DIO]:STKOUS CYCLE IN THE GUINEA-PIG 



CHARLKS R. STOCKARD AND Q. X. PAPANICOLAOU 



PLATE 4 



^ 



u 



:^5 -S-V 



^"V^L'"' s& ■<«^ -<^ €> if^ -^Si 







*3H< 



tJ 



'"^^ 



«^^ 



<7 







5>^. 





13 





273 



