a. Development of urogenital system. Polypterus spec. (Crossopterygii) 

 SMITH. A. S. A.B. — Dept of Zool., Univ. of Calif.. LOS ANGELES 24. 



Cal., U.S.A. 

 SMITH, Miss B. T. — Dept of Biol., Hamilton Coll., McMaster Univ., 



HAMILTON. Ontario, Canada 

 SMITH, S. M.A.. Ph.D. — Univ. Museum of Zool., Univ. of Cambridge. 



Downing St, CAMBRIDGE, England 

 SMITHBERG, M. Ph.D. — Roscoe B. Jackson Mem. Lab.. BAR HAR- 

 BOR, Me. U.S.A. 

 SMRECZYnSKI, S. Ph.D. — Zool. Dept of the Jagiellonian Univ., St 



Anne 6, KRAKOW, Poland 



(no embryological work in progress) 

 SNELLEN, H. A. Med.Dr, Prof. — Anat.-Embryol. Lab. of the Univ. of 



Leyden, Wassenaarseweg, Boerhaavekwartier, LEIDEN, Holland 

 a. Heart and vessels in congenital malformations. Homo sapiens (Prima- 

 tes) (in collaboration with J. DANKMEIJER, Miss A. DEKKER and 



Miss H. C. van INGEN) 

 SNOOK, T. B.S., M.S., Ph.D. — Dept of Anat., School of Med., Univ. 



of North Dakota, GRAND FORKS, N. Dak., U.S.A. 



(no embryological work in progress) 

 SOBELS, F. H. Ph.D. — Genet. Inst, der Rijks Univ., Stationsstraat 9, 



UTRECHT, Holland 

 SOBEY, W. R. Ph.D. — C.S.I.R.O. Anim. Gen. Sect., c/o Dept of Zool., 



Univ. of Sydney, SYDNEY. N.S.W. Australia 

 SOUNHEIN, E. A.B. — Dept of Zool.. Univ. of Calif., LOS ANGELES 



24, Cal., U.S.A. 

 SPIEGEL, M. B.S., Ph.D. — Dept of Embryol.. Div. of Biol.. Cahf. Inst. 



of Technol., PASADENA 4. Cal., U.S.A. 

 SPIRITO, A. Dott., M.I.I.E.. Prof. — 1st. di Biol, gen., Fac. di Med.. S. 



Pietro, PERUGIA. Italia 

 a. Origine e natura dei tumori. Bu[o spec. (Anura) 

 SPOFFORD. W. R. Ph. D.. Prof. — Dept of Anat., School of Med., State 



Univ. of New York, 766 Irving Ave, SYRACUSE 10, N.Y., U.S.A. 



a. Induction and determination in the neural plate. Ambystoma maculatum 

 (Urodela) 



b. Experimental neurogenesis. Ambystoma maculatum (Urodela) 

 SPRATT, Jr, N. T. A.B.. Ph.D.. M.I.I.E., Prof. — Dept of Zool., Coll. of 



Sci., Lit. and Arts, Univ. of Minnesota, MINNEAPOLIS 14, Minn., 

 U.S.A. 



a. Investigating the nutrient requirements essential to morphogenesis and 

 growth in the early stages of development (pre-streak and streak blasto- 

 derms). Gallus domesticus (Aves) 



b. Survey of dehydrogenase enzymes in early embryos: 1. LocaUzation of 

 enzyme activity, 2. Structural integrity and enzyme activity. Gallus 

 domesticus (Aves) 



c. Regeneration. Planaria spec. (Turbellaria) , Tubularia spec. (Coelente- 

 rata) 



d. Cytological study of the developmental center (organizer). Gallus do- 

 mesticus (Aves) 



e. Analysis of mechanism of morphogenetic movements by time-lapse cine- 

 matography. Gallus domesticus (Aves) 



103 



