[11] AVORK AT COLD SPRING HARBOR. 139 



such eggs would never hatch. We invariably noticed this to be the 

 case, and concluded to accept it as prima facie evidence that whenever a 

 cod egg went to the bottom, that was the last of it, so far as its capacity 

 for development was concerned." 



To this I replied : " I have observed that the codfish eggs which I 

 have taken at Fulton Market, New York, had a tendency to sink, as 

 just stated by Professor Ryder. When I removed them irom the pan 

 into ajar, the same thing occurred, and you could see the upper line of 

 the eggs about half way up the jar. When placed in the McDonald 

 hatching jars, they acted like whitefish eggs, except that they were 

 a little lighter. The moment the circulation of the water stopped 

 they all sunk to the bottom. I confess to having been somewhat skep- 

 tical about ' floating eggs ' of codfish, although I understand from Pro- 

 fessor Ryder and Colonel McDonald, tbat at Gloucester the eggs actually 

 floated on the surface, resembling in appearance a honey-comb, and 

 that they were so buoyant that a portion of the egg would literally stand 

 out of the water. I attributed the failure to impregnate the eggs taken 

 at Fulton Market to the shock which the fish suffers by being thrown 

 into the cars from the fishing smacks. They are cast from the deck to 

 the surface of the water, a distance of from 4 to C feet, and usually strike 

 on their bellies. The cod egg is exceedingly delicate, and breaks like 

 a soap-bubble at a touch." 



Colonel McDonald then said: "The fish from which the eggs at 

 Wood's Holl were taken, were, as far as I know, handled very carefully, 

 being transferred from the smack to the car with as little violence as 

 possible. But may not the difference in the results of the observations 

 made at Wood's Holl and Fulton Market, be explained by a difference 

 in the density of the water at the two places ? Of course the buoyancy 

 of the cod egg depends upon the density of the water in which it is 

 placed. Now at Wood's Holl, where the water opens out to the ocean, 

 it surely must be much more dense than at New York Harbor, and the 

 effect of this difference upon the eggs is clearly proved by the fact that 

 those eggs which floated at Wood's Holl sunk at New York. In regard 

 to the eggs taken at New York, they were sent on in hermetically sealed 

 jars to Washington, where on arrival they were found to be impregnated 

 and a small proportion developing. They were then put into salt water 

 artificially prepared (5 ounces of salt to the gallon of water). Devel- 

 opment went on, I think, for fifteen or sixteen days, until the embryo 

 was moving and the heart beating, and yet after all we did not succeed 

 in hatching them. Up to that time their development, I believe, was 

 normal. The embryological investigations were carried on by Profess- 

 or Ryder, who, i)erhaps, will add a few words." 



Prof. Ryder remarked : " You do not mean to say that all the eggs 

 taken were fertile, but that the greater portion of them were. There 

 were large quantities that I know would come to nothing. The vitel- 



