236 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Centriole and Centrosphere in Degenerating Fibroblasts.- — 



Warren H. Lewis {Proc. Amer. Physiol. Soc, dlst Meeting, in Amer. 

 Journ. Physiol., 1919, 49, 123). In the normal fibroblast tbe centriole 

 lies close to one side or one end of the nucleus. The mitochondria do 

 not appear to have any definite relation to it, being disposed more or 

 le s parallel to the long axis. As degeneration in culture proceeds 

 granules accumulate about the centriole, and each granule usually 

 becomes surrounded by a vacuole. The mitochondrial threads and rods 

 become more or less radially arranged about the centriole. A clear area, 

 the centrosphere, develops around the centriole. It is usually quite free 

 from granules, vacuoles and mitochondria. It looks as if the centriole, 

 and not the nucleus, was the centre of metabolic activity. J. A. T. 



Passage of Solids from Nucleus to Cytoplasm. — M. v. Derschau 

 {Arch. f. ZeJlforschimg, 1916, 14, 22, 2 pis.). The passage of sub- 

 stances from nucleus to cytoplasm is believed to be in the main by the 

 diffusion of materials in solution, and, in exceptional cases, by rupture 

 of the nuclear membrane. The author denies the definiteness of this 

 membrane. The boundary of the nucleus is due to larger and more 

 closely packed droplets of basi-chromatin. Solid materials, e.g. of chro- 

 matin, pass readily across the vague nuclear frontier, to form chromidia 

 and the like in the cytoplasm. J. A. T. 



Minute Structure ot Hagfish-skin. — K. E. Schreiner {Arch. 

 Mikr. Anat., 1916, 89, 109, 6 pis., 15 figs.). In the skin of Myxine 

 glutinosa there are indifferent formative cells and thi'ee kinds of gland 

 cells : {a) filament-making, {h) large vesicular mucous, and (c) small 

 cylindrical mucous. A detailed account is given of the minute struc- 

 ture of these elements. The remarkable threads are produced from 

 secreted granules and unite in an axial fibre which extends to the base 

 of the glandular cell. It increases rapidly in length and is coiled in a 

 spiral around the nucleus. The coils of the spiral are so numerous that 

 it is not possible to decide whether the fibre is single or multiple. But 

 this is only the beginning of the intricacy of structure that the author 

 describes. J. A. T. 



New Theory of Symbions. — Paul Portier {Les Symhiotes, Paris, 

 1918, 315, 1 pi., 63 figs.). The author's theory, in support of which he 

 conjures up ingenious evidence, is that all organisms except bacteria, 

 are compound, being made up of the association of two different kinds 

 of living creature. Every living cell includes in its cytoplasm what 

 histologists call " mitochondria." These are really partner bacteria or 

 symbions. The symbion or " symbiote " has two remarkable qualities, 

 an extraordinary plasticity which enables it to adapt itself to the 

 most varied conditions, and an extraordinary power of synthesis. The 

 symbiotic bacteria come from without, and they may in certain cases 

 return to an independent life. In most cases, however, the micro- 

 organism has become irrevocably domesticated, and is unable to live 

 outside of its partner-cell. J. A. T. 



