I. DESCRIPTIVE AND COMPARATIVE EMBRYOLOGY 



KEY 



1 Theoretical problems and general questions 



2 Methods and techniques 



3 Para-emhruological subjects 



a General subjects (e.g. Protozoan development) 

 b Reproduction 



4 Initial development 



b Gametogenesis until completion 



1 Spermatogenesis, sperm 



2 Oogenesis, ovum 



3 Egg membranes 

 c Maturation 



d Ovulation and oviposition 

 e Fertilization 

 f Parthenogenesis 

 g General subjects 



5 Cleavage 



a Cleavage 

 b Cell-lineage 



6 Further development of Evertebrata 

 a General investigations 



1 General subjects 



2 Complete and partial development 



3 Normal tables 

 b Embryogenesis 



1 Pre-gastrulation 



2 Gastrulation 



3 Formation of germ layers 



4 Late embryonic development 

 c Larval development 



d Development of parts of the organism 



1 Head 



2 Limbs and tail 



3 Other parts 



e Development of organ systems and organs 

 (Cf. Key on p. 230) 



7 Further development of Chordata 

 a General investigations 



1 General subjects 



2 Complete and partial development 



3 Implantation, placentation, extra-embryonic membranes 



4 Normal tables 

 b Gastrulation 



1 Pre-gastrulation 



2 Gastrulation 

 c Neurulation etc. 



1 Neurulation 



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