122 ZOOLOGY 



mitochondria. The important point is that the Golgi apparatus 

 appears to produce the yolk nucleus in the early oocyte. This, 

 being albuminous, differs from the previous cases and may be 

 regarded with suspicion. The other accounts of the development 

 of the yolk in Ciona do not agree with this. Hirschler (49) says 

 the yolk nucleus is derived from the cytoplasm and that the 

 Golgi apparatus contributes lipoid material to the yolk droplets 

 formed by a previous swelling of the mitochondria. Neither of 

 these accounts seems entirely satisfactory. 



Lastly, Ludford (74) believes yolk to be formed in Patella by 

 the Golgi bodies in much the same way as the acrosome. 

 This appears to fit in with the theory enunciated above, and 

 certainly conforms most nearly with the Process theory of 

 action. 



Summarising now the present position as regards the function 

 of the Golgi apparatus in animal cells, we find a general 

 tendency for this cell inclusion to act as a centre of synthesis. 

 The actual substance of the apparatus does not seem to take any 

 material part in the process of synthesis except as an enzyme or as 

 the producer of enzymes. In a review of the behaviour of the 

 Golgi apparatus in various types of cells it has been shown that 

 many different kinds of substances may arise as deuteroplasmic 

 inclusions as the result of its activity. Even in the single class 

 of the gland cells, mucous, serous and lipoidal secretions, all arise 

 from the activity of the Golgi apparatus. In the male germ cell 

 the watery acrosome is produced by the Golgi complex, and in the 

 female germ cell there is a growing body of evidence to show 

 that some of the yolk (lipoidal) at any rate is formed by the Golgi 

 elements. The same marked contrast between the characters of 

 the products can be seen in the nerve cells, where formation of 

 the Nissle granules is apparently the function, and in the thyroid 

 gland, activity or the resynthesis of fats from the fatty acids and 

 glycerol in intestinal cells. 



Having regard to this great variety of the products of Golgi 

 activity, it is only in general terms that any working hypothesis 

 can find expression at present. It seems likely, however, that in 

 the future, with the continued elaboration of technique and the 



