Bretscher 16 Burns 



b. Development of the leg; influence of colchicine. Gallus domesticus 

 (Aves) 



c. Development of the leg; influence of the epidermis. Gallus domesticus 

 (Aves) 



d. The development of skeleton and muscles of the pelvic-girdle and hind 

 limbs. Xenopus laevis (Anura) (Normal Table) 



BRETSCHNEIDER. L. H. — Zool. Lab., State Univ. of Utrecht, Fac. of 



Sci., Janskerkhof 3, UTRECHT. Holland. 



(no embryological work in progress) 

 BRIEN, P. L. F.I.I.E., Dr, Prof. — Lab. de Zool.. Fac. des Sci.. Inst, de 



Zool. Torley-Rousseau, Univ. libre de Bruxelles, 50 Av. F.D. Roosevelt, 



BRUXELLES, Belgique. 



(no data received on Nov. 1^*. 1952) 

 BRIGGS, R. W. Ph.D. — Lankenau Hospital Research Inst, and Inst, for 



Cancer Research, Burholme Ave, Fox Chase. PHILADELPHIA 11, Pa, 



U.S.A. 

 a. The problem of nuclear differentiation, investigated by means of trans- 

 plantation of embryonic cell nuclei into enucleated eggs. Rana (Anura) 



(in collaboration with T. J. KING) 

 BRIONES. H. M.D. — Inst, de Biol. ..Juan Noe". Univ. de Chile, Casilla 



2988. SANTIAGO. Chile, 

 a. Interspecific transfer of eggs. (Rodentia) 

 BROERS. C. J. M.Sc. — Anat.-Embryol. Lab. der Rijks Univ., Janskerkhof 



3. UTRECHT. Holland, 

 a. The development of the tympanic region and skull. (Mammalia) 

 BR0NDSTED. H. V. F.I.I.E.. Dr Phil.. Prof. — Inst, for Aim. Zool., Uni- 



versitetsparken 3, COPENHAGEN p, Denmark. 



(no embryological work in progress) 

 BRUNER, TAiss J. A. Ph.D. — Zool. Dept. State Univ. of Iowa. IOWA 



CITY. Iowa. U.S.A. 



a. Hormones and sex differentiation. Ambystoma (Urodela) 



b. Respiratory metabolism of eggs. Rana pipiens (Anura) 



c. Natural causes of teratogenic development. (Mammalia) 



BUCHER. N. — Zool.-vergl.Anat. Inst., Naturw. Fak., Univ. Zurich, 



Kiinstlergasse 16, ZURICH 6. Schweiz. 



(no data received on Nov. 1**, 1952) 

 BUNO. W. F.I.I.E., B.S., Ph.D., Prof. — Dept de Histol. y Embriol., Fac. 



de Med., MONTEVIDEO. Uruguay. S. America. 



(no data received over some years) 

 BURDON-JONES. C. B.Sc. Ph.D. — Dept. of Zool.. Univ. Coll. of North 



Wales. BANGOR, Caernarconshire. N. Wales (U.K.) 

 a. Embryology. (Protochordata) 

 BURNS. R. K. F.I.I.E.. A.B.. Ph.D.. — Dept of Embryol., Carnegie Inst, of 



Washington, Wolfe and Madison Strs. BALTIMORE 5. Md. U.S.A. 



— Hon. Prof, of Zool., Dept of Biol., The Johns Hopkins Univ.. BAL- 

 TIMORE 18. Md, U.S.A. 



a. The experimental control of sex differentiation in the embryo by means 

 of hormones. Didelphys virginiana (Marsupialia, Mammalia) 



b. A study of gonad modifications induced by hormones, and the reactions 

 of the gonoducts and urogenital sinus to hormones. Didelphys virginiana 

 (Marsupialia, Mammalia) 



