163 



and direction of sectioning, method of staining, etc.) and numbered 

 according to given indications. 



3. Costs of transport may be charged in case these surpass reasonable 

 hmits. 



4. Two copies of those pubhcations deahng with material from the Central 

 Embryological Collection should be sent to the Central Embryological 

 Library of the Hubrecht Laboratory. 



5. In case material of the Central Embryological Collection has been used 

 in investigations, it is respectfully requested that this be indicated in 

 the pubhcations concerned. 



Restrictions: 



6. Very rare or regularly consulted material can only be studied at 

 the Hubrecht Laboratory. 



7. Material belonging to the historical collection cannot be lent out. 



8. In case material has not been treated properly or (after special request) 

 has not been returned in time by an investigator, material will no longer 

 be lent out to him or her. 



IV The Photographic Reproduction Service 



The Hubrecht Laboratory is willing to make photographic reproductions 

 of any papers which are present in the Central Embryological Library or 

 can be borrowed from elsewhere. These reproductions will be either 

 positive transparent microfilm prints (for use in a 

 microfilm reading apparatus) or enlarged ordinary prints. The 

 negatives will remain at the Hubrecht Laboratory. 



We have been experimenting to find the most suitable materials and the 

 best methods for reproduction. The result is the following price-list (prices 

 per page, both text and plates): 



positive film prints: fl. 0.25 = $ 0.07 



7 X 10 cm. (box-camera size): fl. 0.40 = $0.10 



13 X 18 cm. (ordinary page size): fl. 0.50 = $0.13 



18 X 24 cm. (large page size): fl. 0.65 = $0.17 



V The Normal Table o f Xenopus laevis 



Dr D. R. Newth (London) has untertaken the description of the develop- 

 ment of muscles and skeleton of the pelvic girdle and hind hmbs. Miss M. T. 

 C. van Egmond (Utrecht) will study the development of the ear. Dr Bretscher 

 (Bern) and Dr van de Kamer (Utrecht) have withdrawn from the project. 



The present situation of the project is as follows: 



We received the contributions of Dr Newth (London), Dr Smit (Stellen- 

 bosch), Dr Ryke (Potchefstroom), Prof. Raven (Utrecht), Dr Kollros (Iowa 

 City) and Dr Nieuwkoop (Utrecht). 



The contributions of Dr Millard (Cape Town), Prof. Ariens Kappers 

 (Groningen) and Dr Bijtel (Groningen) are nearly completed. 



The subjects of the other collaborators are still in preparation; most of 

 them make satisfactory progress. 



