56 CALIFORNIA ACADEMY OF SCIENCES. [jd Ser, 



structures described by Butschli and v. la Valette, and calls 

 attention to the great resemblance between them. From 

 this we may conclude that of the cytoplasmic spheres de- 

 scribed by me above, the granosphere is the most constant, 

 probably existing in all the cells. 



The large granular spheres which have been described 

 by Meves from the achilles tendon of the frog must also 

 be considered identical with some of the spheres of the 

 plasmocyte. Meves describes the large outer sphere — my 

 granosphere — as concentric layers of indistinct granules 

 which might be considered as membranous formations sur- 

 rounded by thin homogenous cytoplasm. There can be lit- 

 tle doubt that the above structure is identical with my 

 granosphere, in which similar concentric layers are fre- 

 quently observed (Meves, Taf. ix, fig. 2, etc.). In his fig. 

 10 there appears a pale uncolored sphere surrounding the 

 centrosomes (but inside the centrosphere), which probably 

 corresponds to my somosphere. We must remember that 

 Meves used iron stain which does not differentiate as well 

 as the toluidine. 



Especially as regards the somosphere, I think that future 

 investigations will demonstrate its presence in the micro- 

 centrum of many cells, and that many structures which 

 have been described as centrosomes will, when subjected to 

 closer examination, be referred to the somosphere; for in- 

 stance, the branched centrosomes in the pigment cells 

 described by Zimmermann. A real somosphere has been 

 observed by Hacker in the winter egg of Sida crystallina 

 (loc. cit., Taf. xxi, fig. 1), which he calls after Strassburger 

 " tingirbare innenzone." The increase in size and growth 

 of the centrosome in Sida is also pointed out by Hacker, a 

 growth which is probably analogous to the growth of the 

 somosphere in the plasmocyte. 



Whether there exists any homology between the plasmo- 

 cytes and the paranuclei described by Bremer from the 

 blood of Testudo Carolina must remain undecided. Judg- 

 ing from the figures accompanying Bremer's paper, as well 

 as from his descriptions, the paranuclear bodies are much 



