Alytes obstetricans 

 (March-Apr.) 



Bombina bombina 



Bombina variegata 



Bufo americanus 



Bufo bufo (March-Apr.) 



Bufo marinus 



Bufo terrestris 



Bufo valliceps (Apr. -July) 



Discoglossus pictus (March- 

 June; Nov. -Dec.) 



Discoglossus pictus 

 (Jan. -June) 



Hyla arborea 



Hyla cinerea 



Hyla crucifer 



Phrynosoma spec. 



Rana catesbeiana 



Rana clamitans 



Rana dalmatina 

 (March-Apr.) 



Rana dalmatina 



Rana esculenta 



Rana palustris 



Rana pipiens 



Rana pip. sphenocephala 

 (Febr.-May) 



Rana pip. sphenocephala 



Rana sylvatica 



The supply of Aves and Mammalia is covered by the "International Com- 

 mittee on Laboratory Animals" (Hon. Executive Seer.: Dr. W. Lane-Petter, 

 Laboratory Animals Centre, M.R.C. Laboratories, Woodmansterne Road, 

 Carshalton, Surrey, England). 



2 ) 



13) 

 15) 

 16) 



in exchange for Pipa americana 

 in exchange for Anolis carolinensis 

 in exchange for Hyla (fixed stages) 

 in exchange for Ambystoma mexicanum 



B. LIST OF NAMES AND ADDRESSES 



(geographical order) 



N. A M E R I C A 

 United States 



1. DEPT. OF BIOLOGY, Wesleyan Univ., MIDDLETOWN, Conn. 



2. ARGONNE NAT. LAB, 9700 South Cass Ave., ARGONNE, 111. 



3 Dr. E. KRUGELIS-MacRAE, DEPT. OF ANAT., Univ. of Illinois, 

 1853 W. Polk St., CHICAGO 12, 111. 



259 



