372 Charles R. Stockard. 
favorable results were obtained in solutions of 16, 17, 18, 19, 20, 
21 and 22 ce. of molecular MgCl, made up to 60 ce. by the addition 
of a sufficient amount of pure sea-water; e.g., 44 cc. of sea-water 
was added to the 16 ec. of molecular MgCl, and 43 cc. of sea-water 
to the 17 cc. of MgCl.. The solutions are, therefore, ¢0, tb Go» 
ete., parts MgCl. to sea-water. In the ¢o solution 66 per cent 
of the embryos were cyclopean in one of the experiments. Eggs 
were exposed to the action of Mg shortly after fertilization and at 
various other times until they reached an early periblast stage, or 
were fourteen hours old, all with similar results. Although the 
most favorable time for introducing the eggs into Mg solutions 
is during the eight-celled stage. The developing embryos were 
returned to pure sea-water after the third day. “The Mg is so 
slightly toxic that eggs may be kept in it and will continue to 
develop; the embryos actually hatch and swim about in the solu- 
tion, being, however, slightly slower in their developmental rate 
and not so hardy as the specimens which are returned to the sea- 
water. 
Tue AcTION OF ALCOHOL ON DEVELOPMENT 
Weak solutions of alcohol exert a most decided effect on the 
_developing fish embryos, causing deformities of the central nervous 
system, the eyes, and ears in a very large percentage of the speci- 
mens. 
a. Defects of the eyes 
Typical cases of cyclopia showing in the different specimens 
all gradations, from merely closely approximated eyes, hour-glass 
eyes with two pupils and two lenses, oval eyes having the two 
component intimately associated, typical median cyclopean eyes 
with scarcely an indication of their double nature and extremely 
small ill-formed cyclopean eyes, were present in the weak alcohol 
solutions. All of these have been fully described in a former 
‘paper (’09) on the artificial production of cyclopea as a result of 
the action of Mg. The alcohol monsters in some cases also 
‘present various degrees of the monophalmicum asymmetricum 
