EXPLOSION OF SPERMATOZOA OF LOPHOPANOPEUS BELLUS. 289 



obtain a plentiful supply of living spermatozoa was to rupture 

 the deferent ducts and the male gametes oozed out in tremendous 

 numbers. 



The living spermatozoa were studied in the same manner as 

 described in my earlier paper on the spermatogenesis of the 

 edible crab, Cancer magister Dana (Fasten, 1918). Numerous 

 spermatozoa suspended in the crab's body fluid, or in sea water 

 which is isotonic with the crab's body fluid, were placed on a 

 slide and covered .with a cover glass. These could then be 

 studied with the high power oil-immersion lenses. By allowing 

 various chemical solutions to diffuse under the cover glass all 

 changes in the spermatozoa could be observed and outlined with 

 the aid of the camera lucida. 



The living spermatozoa were studied in the following solutions: 



1. Crab's body fluid. 



2. Sea water. 



3. Sodium chloride (NaCl) M/2 NaCl and less, 



4. Sodium nitrate (NaNO 3 ) M/2 NaNO 3 and less. 



5. Calcium chloride (CaCl 2 ) 3/8M CaCl 2 and less. 



6. Potassium chloride (KC1) M/2 KC1 and less. 



7. Potassium nitrate (KNO 3 ) M/2 KNO 3 and less. 



8. Potassium hydroxide (KOH) -very dilute solution. 



9. Distilled water. 



10. Cane sugar (Ci 2 H 22 Oii) -M/i Ci 2 H 22 On. 



u. Ovarian fluid. 



12. Acidulated sea water. Various small amounts of acids 

 were added to sea water, such as : glacial acetic, sali- 

 cylic, saponin, sodium glycocholate, nitric, hydro- 

 chloric, oxalic, tannic, picric, and chromic acids. 



Many of the spermatozoa in all stages of explosion were fixed 

 on the slide with either osmic acid fumes, or Bouin's fluid, or 

 Flemming's mixture, and then stained with Heidenhain's iron- 

 haematoxylin and acid-fuchsin. Those fixed with osmic acid 

 fumes gave beautiful results, so that the stained elements were 

 perfect representations of the living structures. This can be 

 clearly seen when one examines Figs. 3-7, which are from stained 

 preparations fixed with osmic acid fumes, and compares them 

 with figures I and 2 which are from living spermatozoa suspended 

 in the bodv fluid of the crab. 



