1822 Journal of Applied Microscopy 



from these experiments) its action probably is dependent on its being delivered 

 directly to a point within the egg. Winkler's results on the same subject 

 are thought to be due to the effects of osmotic influences. R. p. 



Loeb, J. Studies on the Physiological Effects The development of the eggs of Fun- 

 of the Valency and possibly the Electrical ^^^^^ ^^g ^^g^ ^S ^ ^gSj. f^^ ^^e tOxic 

 Charges of Ions. I. — The Toxic and Anti- j ^.v • « * r u • i t*. 



toxic Effects of Ions as a Function of their ^nd antitoxic effects of chemicals. It 

 Valency and possibly their Electrical was found that the deleterious effect 

 Charge. Amer. Jour. Physiol. 6:411-433, (tOxic) of a solution of a single electro- 

 ^902. lyte on these eggs could be counter- 



acted by the addition of small amounts of some other electrolyte (antitoxic 

 action). For example, no eggs will develop in a |^m solution of NaCl, but if 

 to 100 c. c. of this solution, 4 c. c. of an ^ solution of CaSO^ be added, 75 

 per cent, of the eggs will develop and form embryos. Experiments of this sort 

 were tried with a variety of chemicals and the somewhat remarkable general re- 

 sult was obtained that the marked toxic action of the salts of monovalent kations 

 (Na, Li, K, NH4) with monovalent anions (CI, NO 3, CH3COO) could be an- 

 nihilated by the addition of a small amount of salt having a bivalent kation (Ca, 

 Ba, Zn, Bo, Pb). For NaCl, trivalent kations (Al, Cr) have a more energetic 

 antitoxic effect than bivalent kations. Anions of whatever valency were not 

 found to have this antitoxic effect. The author inclines to the view that in the 

 case of NaCl the CI ion may be the one to which the toxic effect is due, although 

 in previous papers he has advocated the opposite position. From the fact that 

 in a series of sodium salts the toxicity increases with the increase in the valency 

 in the anion, Loeb concludes that the poisonous effects of salts with a univalent 

 kation are due to the negative charges (or negative electrons) of the anions. 



In concluding, the author develops the view that the electrical charges of ions 

 produce their effect on life phenomena by changing the physical condition (coag- 

 ulating or liquefying) of the colloidal material of which protoplasm is in the main 

 composed. R. p. 



Loeb, J. and Lewis, W. H. On the Prolonga- Unfertilized eggs of the sea-urchin lose 

 tion of the Life of the Unfertilized Egg of ^^gij. gj. ^f developing in about 



Sea-Urchins by Potassium Cyanide. Amer. ^ ^ ^^ , -r ,.1. 1 /^ • 



Jour. Physiol. 6: 305-317, 1902. twenty-four hours if they are left in 



ordinary sea water after deposition. 

 The authors of this paper found that by subjecting these unfertilized eggs to the 

 action of a mixture of about 100 parts of sea water and one part of an y^ KCN 

 solution for a varying length of time their power of development' could be 

 preserved for a much greater period than when they were left in the sea water 

 alone. The maturated but unfertilized eggs were taken from the animals and 

 placed in the KCN solution. After they had remained for some time in this 

 solution they were transferred to ordinary sea water and fertilized. It was found 

 that by gradually diminishing the strength of the KCN as the experiment pro- 

 gressed it was possible to obtain plutei from eggs which had been subjected to 

 the action of this solution for as long as 112 hours. It was also possible to in- 

 duce parthenogenetic development in eggs which had been subjected to the 

 action of KCN in a similar manner. The authors believe that there are going 

 on in the unfertilized egg " specific mortal processes," which, unchecked, lead to 

 its rather speedy dissolution. Normally fertilization checks or modifies these 

 processes. In the experiments described in this paper these processes are 

 checked by the poison KCN. It is to be regretted that the authors chose to 

 designate as " prolongation of life " a process which is evidently, as they them- 

 selves admit, nothing more than a suspension of vital activities for a certain 

 time (" vie latente "). Such phenomena are, of course, well known in other 

 cases. . R. P. 



