367 



Table 7, 





Time. 



FUNDULUS X FUNDULUS. 



FtTNDULUs X Stenostomus. 



10.50 A. M. 



July 11. 



Fertilization. 



Fertilization. 



11.37 A. M. 



, July 11. 



Begin. 2 cells. 



Begin. 2 cells. 



11.55 A. M. 



July 11. 



Compl. 2 cells. 



Compl. 2 cells. 



12.05 p. M. 



July 11. 



Begin. 4 cells. 



Begin. 4 cells. 



12.35 p. M. 



July 11. 



Compl. 4 cells. 



Compl. 4 cells. 



12.40 p. M. 



July 11. 



Begin. 8 cells. 



Begin. 8 cells. 



1.00 p. M. 



July 11. 



Compl. 8 cells. 



Compl. 8 cells. 



1.05 p. M. 



July 11. 



Begin. 18 cells. 



Begin. 16 cells. 



11.00 P. M. 



July 12. 



Late cleavage. 



Late cleavage. 



1.25 P. M. 



July 12. 



Vi'ell developed germ ring and 

 shield i over. 



Some begin, of germ ring. 



3.30 p. M. 



July 12. 



i over yolk. 



i over yolk. 



7.20 p. M. 



, July 12. 



3 over yolk. 



1 over yolk. 



8.00 A. M. 



July 13. 



Blast, closed. 



Most nearly closed. Embryos 

 too°short. 



1.00 p. M. 



July 13. 





No further along. 



Fundulits heterocUtus, female, 

 X 



Eupomotis gibbosits, male. 

 This cross was attempted six times, only three of which were success- 

 ful. The number of eggs impregnated each time was very small. I do 

 not think this was due to the condition of the milt, because an abundance of 

 apparently good milt was used. The dry method was used and the eggs 

 kept in fresh water. 



Experiment 7 Less than 1 per cent. 



8 " " 1 " " 



21 " " 1 " " 



The eggs were followed to about one-third to one-half over the yolk 

 when they stopped development. An embryonic ring and shield were devel- 

 oped, but the protoplasm did not look normal even in earlier stages of gas- 

 trulation showing a relatively opaque appeai'ance compared with normal 

 eggs. 



The reciprocal of this cross was not attempted owing to a failure to get 

 ripe eggs of the sunfish. 



