I/O 



Charles R. Stockard 



After seventy hours those that spent one hour in the molecular 

 solution produced some living embryos, and though well formed 

 they were slower than the control in their rate of development. 

 Those that remained in this solution for two hours showed only a 

 few living eggs with badly stunted embryos. Of those from the 

 double molecular solution of LiCl, after one hour, only one in 

 twenty was alive, and this one was stunted. 



Solutions of double molecular and one and one-half molecular 

 strengths were prepared with sea-water and an experiment similar 

 to the above was conducted with like results, although the eggs 

 recovered somewhat more readily after being removed from these 

 solutions and returned to pure sea-water. This latter fact may 

 indicate that some of the salts of the sea-water tend to counteract 

 in part the effects of the LiCl. 



At first sight the above results seem to contradict my former 

 statement to the effect that eggs removed from Li solutions in 

 three, four or five hours showed no toxic effects in their later devel- 

 opment. It is recalled, however, that the solutions then used were 

 weak ones, while the above are strong enough to kill all eggs 

 remaining in them. 



Such results as these can leave, I think, no doubt as to the fact 

 that the membrane of Fundulus heteroclitus eggs is readily per- 

 meable to salts during the first few hours of their development. 

 The permeability of this membrane at later stages is also beyond 

 question, and probably it becomes more readily permeable as 

 development advances. 



THE DEVELOPMENT OF FUNDULUS EGGS OUT OF WATER 



The only reference hitherto made to the development of Fun- 

 dulus eggs out of water is that by Morgan ('06), to the effect that 

 these eggs will develop on a glass plate in a moist atmosphere. 

 I undertook to rear embryos in this fashion to ascertain what 

 abnormalities, if any, would result from such treatment. The 

 most interesting result obtained was that although these fish 

 develop to all appearances in a perfectly normal manner, except at 

 a little faster rate, they are entirely utiable to hatch while on the 

 moist plates. Eggs were kept from June 30 until August 2 in a 



