138 CYTOPLASMIC INCLUSIONS 



seem to be temporary reserves, while the refractive bodies are the final 

 reserves. In the blebs, the protein portion appears later than the lipoid 

 portion. There is no evidence in these cases of anything more than the 

 accumulation of materials. 



GoLGi Bodies 



The term Golgi body has been applied in Protozoa to organelles 

 which differ fundamentally in both composition and function. These 

 structures include contractile vacuoles (Ramon y Cajal, 1904-5), gran- 

 ules (Hirschler, 1914), specialized regions of cytoplasm around the 

 contractile vacuoles (Nassonov, 1924), segregation granules (Cowdry 

 and Scott, 1928), osmiophilic nets (Brown, 1930), and the parabasal 

 apparatus (Duboscq and Grasse, 1925). The controversies which have 

 arisen between advocates of one or another of these structures have 

 been due not so much to disagreement upon the actual facts involved as 

 to disputes concerning criteria for the identification of Golgi material. 

 The selection of criteria is thus a crucial point in coordinating the in- 

 vestigations of Golgi bodies; yet even after years of work on representa- 

 tives of all the major groups of animals and plants, and notwithstand- 

 ing periodic reviews of the field, few criteria seem to have unanimous 

 approval — few, indeed, have majority approval. The most recent re- 

 view (Kirkman and Severinghaus, 1938) after failing to demonstrate 

 any universal and objective basis of identification, quotes as follows 

 from Gatenby (1930): "modern workers in general have experienced 

 no difficulty in identifying Golgi bodies." This is very satisfactory as 

 long as only one school of cytologists is considered, but such state- 

 ments lose their attractive ring of authority when one tries to correlate 

 the results presented by such experienced cytologists as Bowen, Parat, 

 Gatenby, Canti, or Ludford, to mention only a few. 



This is particularly true when seeking criteria on which to base a 

 reasonable identification of Golgi bodies in the highly specialized cells 

 of the Protozoa. In the following paragraphs the major objective cri- 

 teria which have been used are discussed with particular reference to 

 their applicability to the Protozoa. In general these criteria involve two 

 points — consistent impregnation, and occurrence in all types of cells. 



The first Golgi structures were discovered by the use of metallic im- 

 pregnation methods, and ever since these methods have remained as 



