DERIVED ORGANIZATION 113 



lates and hemosporidia, which he called the "Biiiucleata." 1 As 

 Doflein points out, not only do the hemosporidia have no blepharo- 

 plasts as do the trypanosornes, but blepharoplasts in the latter are 

 not to be considered nuclei. In this use of the term blepharoplast 

 Doflein includes the structure to which Woodcock gave the name 

 kinetonucleus, but he employs the term in a special sense as a 

 kinetic element, while German writers generally use it for structures 

 of widely different significance. Thus Schaudinn, although con- 

 vinced of its nuclear character, nevertheless called it a blepharo- 

 plast. French writers, as a rule, speak of it as a centrosome (e. g., 

 Mesnil, Laveran, etc.) as do some English observers (e. g., Moore 

 and Breinl) ; many of the latter, however, follow the original nuclear 

 interpretation, Bradford and Plimmer following Stassano, regarding 

 it as a " micronucleus " and comparing it with the smaller nucleus 

 of the ciliates, while Woodcock and Minchin considered it a "true 

 nucleus." 



The essence of the problem indicated by the various usages of 

 these familiar terms comes down to a decision as to whether the 

 so-called kinetonucleus, by which is meant the relatively large 

 chromatoid body in the cytoplasm and closely connected with the 

 basal granule, is a nucleus, or a kinetic center of the cell, or neither. 

 Woodcock's term connotes a happy combination of both nuclear and 

 kinetic possibilities; the kinetic function evident from its relation to 

 basal granules or blepharoplasts, while its nuclear characteristic is 

 seen mainly in the deeply-staining chromatin-like substance of which 

 it is composed as well as by its frequent connection with the nucleus. 

 Some writers, notably Rosenbusch (1909), giving free play to the 

 imagination, and under the conviction that it is a nucleus, describe 

 it as such, with centriole, "karyosome," nuclear space which may 

 contain chromatin granules, and a nuclear membrane. The 

 extremely minute size of this organoid and the pranks which the 

 Romanowsky stain or any of its modifications may play with it, as 

 they do with structures of the actual nucleus, together with a fertile 

 imagination, are sufficient to account for the perfect nuclear type 

 which Rosenbusch, for example, described. Other observers, while 

 maintaining its nuclear character, do not accept this extreme inter- 

 pretation; Minchin, for example, describes it as a "mass of plastin 

 impregnated with chromatin staining very deeply, rounded, oval, 

 or even rod-like in shape" (Prot., p. 2SS). 



If we bear in mind the many types of granules in the cell which 

 stain like chromatin with certain dyes, it seems unnecessary, to say 

 the least, to make the term nucleus, which stands for a well-known 

 and easily recognized organoid of the cell, elastic enough to embrace 

 cytoplasmic bodies in regard to which there is so little evidence of 

 nuclear structure or nuclear function. In well fixed and stained 



1 For critiques of the Binucleata, see particularly Minchin (1912), Dobell (1911). 

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