8o 



A. J. GOLDFARB. 



and the resulting larvse were perfect though small, or incom- 

 pletely, and twin or fused plutei were produced as described by 

 Loeb, Morgan and Driesch. When the eggs were kept in the 

 solution for one hour, each of the four quarter blastomeres 

 developed, some into dwarf plutei, others never beyond the 

 gastrula stage. With increasing exposure to the calcium-free 

 sea water, the increasing diminution in the size of the blasto- 

 meres, and the probable increasing segregation of formative 

 stuffs, plutei were no longer formed, and abnormal embryos were 

 correspondingly more numerous, most of which died early. 



Solutions made with tap water (Woods Hole, Mass.) were 

 highly injurious, for few eggs developed into normal larvae. 

 With distilled water practically all were normal, provided the 

 eggs were not left in the solution longer than about thirty 

 minutes as shown in Table IV. 



The effect of calcium-free 

 No. Experiment. 



266 10 Left in solution, 

 ii 

 12 



13 



TABLE IV. 



sea water upon the development of fertilized eggs. 



Result. 

 Dead. Accident. 



18 



I 



2 



3 

 4 

 5 

 6 



24 

 25 

 26 



27 

 28 



17 

 18 



19 



20 

 21 



Membranes removed. 

 Left in solution. 



Distilled Water. 

 Left in solution. 



Tap water. 

 Left in solution. 



15 mm. 



30 Same as controls and small plutei. 



45 More small plutei and non-developing 



blastulge. 



60 Only small plutei. Very many irreg. 



90 Few small plutei. Most irreg. on 



bottom, dead. 



1 20 Few small plutei. Most irreg. on 



bottom, dead. 



15 Norm, and small plutei. 



30 Dead. Accident. 



65 Norm, and small plutei. 



60 Dead. Accident. 



90 Plutei and irregular clusters. 



105 Some plutei, most irregular, clusters. 



y<2. hr. Norm, and small plutei. 



I Small plutei and irregular plutei. 



2^ Few small plutei. Most irregular. 



6 Most irreg. Nearly all dead. 



7 Most irreg. Nearly all dead. 



]/2 hr. Few norm, plutei. 



1 Irregular plutei and irregular gastrulae. 



2 y-i Only blastulae irreg. 



6 Only blastulse irreg. 



7 Only blastulae irreg. Few alive. 



