ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 337 



the central portion of the scale one can determine with al«olute accuracy 

 the number of years which each salmon has spent in the river as a parr. 

 It does not matter whether the fish weighs five pounds or fifty, the 

 parr-life is indelibly marked on almost every scale. The majority of parr 

 in the River Wye migrate to the sea as smolts at the commencement 

 of the third year of their life. A small proportion may migrate when 

 only one year old, and a still smaller proportion will remain three years 

 in the river before they reach the smolt stage. The earlier the parr 

 becomes a smolt the more probability there is of it reaching the sea 

 and becoming a salmon. If anything is proicticable, there should be 

 encouragement of the stock which produces one-year smolts. J. A. T. 



Functions of Nucleus. — Vernon Lynch {Amer. Joiirn. Physiol. 

 1919, 48, 258-83). An amoeba from which the nucleus has been 

 removed may at times exhibit perfectly normal movement ; in general, 

 however, movement is somewhat affected by removal of the nucleus. 

 An amoeba deprived of its nucleus lives almost as long as an amoeba 

 deprived of food. Evidence is adduced that an amoeba can use glucose 

 in solution as a food. There is also evidence that amcBbaB can synthesize 

 glucose and urea, or some derivatives of these substances, to form a 

 product which is of nutritive value. Glucose is also of some benefit to 

 the enucleated amoeba, but the supposed synthesis of glucose and urea 

 cannot be effected. The non-nucleated cell is injured more quickly by 

 either a lack or an excess of oxygen than is the normal nucleated cell ; it 

 is somewhat more susceptible to high and low temperature than the 

 nucleated cell. 



" The enucleated cell may move, respire, digest, respond to stimuli 

 and exhibit any activity which is dependent solely upon katabolic or 

 destructive processes of protoplasm. The group of phenomena it never 

 shows are those of growth and of regeneration and division. The 

 phenomena of growth are essentially phenomena of organic synthesis, 

 and the dependence of growth upon the niacleus implies the dependence 

 of organic synthesis upon the nucleus." J. A. T. 



Degeneration of Fibroblasts of Chick Embryos in Cultures. — 

 Warrex H. Lewis {Bull. Johns Hopldns Hospital, 1919, 30, 81-91, 

 21 figs.). In fibroblasts in tissue-cultures degeneration granules and 

 fluid vacuoles appear. The author states the characteristics of these in 

 detail. As the cultures get older there is a gradual increase in number 

 and size of the granules and vacuoles. The author discusses the size 

 and shape, the relation of granule and vacuole, the movements (different 

 from and more extended than the ordinary mitochondrial movements), 

 the changes they undergo, the mitochondria and mitochondrial vesicles. 

 He describes the accumulation of granules, vacuoles, and mitochondria 

 about the centriole, and the accumulation or building up of an increased 

 amount of what seems to be a special type of cytoplasm about the 

 centriole. This would indicate that the activities of the centriole are in 

 some manner increased during the degeneration of the cells. Very 

 important is the general suggestion that the living part of the cell 

 cannot be stained by any of the so-called vital dyes, that living proto- 



2 A 



