JOUENAL 



OF THE 



ROYAL MICROSCOPICAL SOCIETY. 



JUNE, 1921. 



THAN 8 ACTION 8 OF THE 80CIETY, 



IV.— THE BEHAVIOUE OF THE NUCLEOLUS DURING 

 OOGENESIS, WITH SPECIAL REFERENCE TO 

 THE MOLLUSC PATELLA.* 



By ReTginald James Ludford, B.Sc. (Lond.), F.R.M.S., 

 Department of Zoology, University College, London. 



(Read Fehruary 16, 1921.) 

 Two Plates. 



Introduction. 



In a previous paper on the Oogenesis of Patella {11)] the relation 

 of the Golgi Apparatus and Mitochondria to the formation of yolk 

 ■was described, and it was mentioned that during that process there 

 was an extrusion of " solid " nucleolar material from the nucleus 

 into the cytoplasm. The present paper is devoted to an account 

 of the behaviour of the nucleolus and the changes in the chromo- 

 phility of the cytoplasm during oogenesis. 



This research, as the former, was carried out in the Zoological 

 Laboratories of University College, London, and my thanks are 

 due to Dr. J. Bronte Gatenby, Lecturer in Cytology, for his kindly 

 interest and helpful suggestions during the course of this investi- 

 gation. 



I have also to thank Mr. H. Graham Cannon, of the Imperial 

 College, for some help with the literature of the subject, and Mr. 



* The cost of the materials used in this research was defrayed by a Govern- 

 ment Grant of the Royal Society, for which I express thanks. 



t The figures in brackets refer to the bibliography at the end of the paper. 



K 



