294 NATHAN FASTEN. 



acids were used. If the acid was a liquid, the dilution used was 

 i part of the concentrated acid dissolved in 25 parts of sea water. 

 A drop of this was then added to the edge of the cover glass 

 under which the living spermatozoa were held suspended in sea 

 water. If the acid used was crystalline in texture, then a few 

 of the crystals were placed at the edge of the cover glass and 

 allowed to dissolve slowly undei 1 it. 



(a) Glacial Acetic Acid. -Causes the protoplasmic cups to 

 lose their granular and vacuolated appearance. Usually two or 

 three dark granules remain in the nuclear cup. The nuclear 

 cups and radial arms swell and lose their color (Figs. 40 and 41). 

 The spermatozoa in many instances are thrown together into 

 aggregates (Fig. 42). After remaining exposed to the action of 

 the acid for some time many of the spermatozoa explode (Fig. 

 43) and disintegrate completely. 



(b) Salicylic Acid. Reaction here is similar to that caused 

 by glacial acetic acid. 



(c) Saponin. Causes considerable swelling (Fig. 44). Nu- 

 clear cup and radial arms become more homogeneous and much 

 paler in color. They appear almost transparent. A few of the 

 spermatozoa explode after being exposed for some time. 



(d) Sodium Glycocholate. Causes swelling similar to that pro- 

 duced by saponin or glacial acetic acid. During this swelling 

 the vacuoles of the nuclear cup at first enlarge and then disappear, 

 giving the nuclear cup a homogeneous appearance. Soon a 

 violent explosion of vesicles takes place. Nuclear cup now 

 loses its greenish color, becomes ragged and transparent with 

 small dark spots. Very shortly the spermatozoa disintegrate. 



(e) Nitric Acid. -This brings about a homogeneity of appear- 

 ance in protoplasmic cup with considerable shrinkage (Fig. 45). 

 The second vesicle in many cases is everted (Fig. 46). 



(/) Hydrochloric Acid. -The reaction here is very similar to 

 that caused by nitric acid. 



(g) Oxalic Acid. Reaction is similar to that produced by 

 nitric acid. 



(h} Tannic Acid. Reaction is similar to that of nitric acid, 

 with the exception that none of the vesicles are everted. 



(i) Picric Acid. The reaction produced in the spermatozoa 



