UNIVERSITY OF CALIFORNIA PUBLICATIONS 
IN 
ZOOLOGY 
Vol. 9, No. 3, pp. 105-136, pls. 13-17 February 23, 1912 
STUDIES ON EARLY STAGES OF DEVELOPMENT IN 
RATS AND MICH. No. 3 
BY 
E. L. MARK anp J. A. LONG 
THE LIVING EGGS OF RATS AND MICE 
WITH A DESCRIPTION OF APPAR- 
ATUS FOR OBTAINING AND 
OBSERVING THEM* 
(Preliminary Paper) 
BY 
J. A. LONG 
PU tare CLUE LU Leen ea ae a ge ens een cn mcmemee marc nare 106 
Apparatus -.. 
Cages 
Birth-recording apparatus ~....-.-.-.--.----------—-------- 
Constant-temperature box for microscope 
(Orueprl bem sicoyay (URNS EY Soccer e ere see Ere ee CREE eee See Se 
Observations ..... 
Literature cited 
*No. 1 of these studies is Long and Mark, ‘‘The maturation of the 
egg of the mouse,’’ Publ. Carnegie Inst. Wash., 1911. No. 2 is Mark and 
Long, ‘‘Die Reifung der Hier der Maus,’’ Verh. 8, Intern. Zool. Kong., 
Graz, 1910. 
