464 Julia B. Platt, The Development of the Cartilaginous Skull ete. in Necturus. 
Contents. 
Introduction . 
Part I. Procartilage 
a) In review. 
b) Descriptive. 
The mesectoderm in Necturus 11 mm long 
The mesectoderm in Necturus 121/, mm long 
The procartilage in Necturus 15 mm long 
Part II. The cartilaginous skull 
The order of development 
The basal plate 
The skull in Necturus 19 mm long. 
The skull in Necturus 46 mm long. 
Part III. The muscles 
The branchial muscles 
The hypoglossus musculature 
Summary of chief results. 
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