188 



YVETTE W. KUNZ 



The fish used in this investigation were taken from an inbred laboratonj 

 stock. The time lapse between successive broods was, on the average, 35 days| 

 at 22° C and a constant 12 hourly day and night cycle. The time between spawninj 

 and fertilization of a new batch of eggs was estimated at 5 days, which left arl 

 embryonic time of 30 days (Kunz, 1964). Lebistes reticulatus shows no super- 

 fetation, but the developmental stages in any one ovary may vary, especialh 

 during early development. 



Fig. 1 



Breeding tank made of perspex 



In order to observe spawning of individual fish, females were kept in breeding 

 cages (Fig. 1), suspended in separate water tanks. The cages were made of clear 

 perspex, with the lower part of green colour to give the occupants some hiding 

 space. Perforation of the side walls allowed for water exchange. A longitudinal 

 slit at the base allowed the newly born fish to escape being preyed on by the 

 mother. 



After the birth of a brood, the females, which were presumed to be pregnant 

 again, were dissected at intervais of from 3 to 30 days. The embryos were 

 examined under the dissecting microscope and allocated to appropriate develop- 

 mental stages. With watchmaker's forceps the embryos were freed from the 

 follicular and egg membranes and kept in physiological NaCl-solution. Drawings 



