Scientific Proceedings. 



f 



(219) 49 



interesting case of mutation of species with lapse into the parent 

 form after several generations, or the specific characteristics are 

 inadequate and P. candatum and P. aurelia are but variants of one 

 species. The latter is the more reasonable hypothesis and on 

 grounds of priority, the common forms of paramecium should be 

 called Paramecium aurelia. 



Physiologically the form known as P. caudatum is more vig- 

 orous in culture than is P. aurelia. During the time that the 

 cultures were in the P. aurelia phase the division rate was rela- 

 tively low (four divisions in five days), but soon after the change 

 to the caudatum form the division-rate rose to two and a half 

 divisions per day on the average for forty days, which is the 

 highest rate on record. With this physiological difference there 

 was a marked difference in the relative volumes of micronucleus 

 and cell-body but no difference in the relative volumes of macro- 

 nucleus and body. 



27 (119). "Experiments with some saline purgatives given 

 subcutaneously " : JOHN AUER. 



In spite of the large amount of work which has been done 

 regarding the effect of subcutaneous and intravenous injections of 

 saline purgatives, investigators are still in disagreement. To men- 

 tion only the most recent writers, MacCallum 1 claims that " all 

 these salts which act as purgatives when introduced into the stomach 

 or intestines have the same action when injected subcutaneously or 

 intravenously y Eckhardt 2 on the other hand, states that ' ' Die 

 Mittelsalze haben bei unseren Haustieren keine abfuhrende Wir- 

 kung " and that " Im Gegentheil wirken sie, auf diesem Wege 

 einverleibt, haufig verstopfend." Both authors used approximately 

 the same dose, injected the same salts subcutaneously and intra- 

 venously and yet arrived at diametrically opposite results. 



In an extensive series of experiments already published, 

 Meltzer and the author 3 have shown, among other things, that the 

 subcutaneous injection of magnesium sulfate does not produce 

 purgation. In view of the peculiar properties of magnesium salts 

 the investigation was extended to some of the other saline purgatives. 



MacCallum, J. B. : American Journal of Physiology, 1904, x, p. 101. 



2 Eckhardt : Inaugural Dissertation, Giessen, 1905. 



3 Meltzer and Auer : American Journal of Physiology, 1905, xiv, p. 366. 



