438 BULLETIN OP THE UNITED STATES FISH COMMISSION. 



by some experiments made by me last summer ; and I will here give a 

 In ief report on the same. 



On July 8 I took about 200 eggs from a lobster which I had for some 

 time kept in a small fish-tank. About two thirds of these eggs I placed 

 in a glass of water, over the open end of which I tied a piece of gauze, 

 and then suspended the glass in the sea, bottom upward. As the roe 

 of the lobster is heavier than water, it of course sunk down and re- 

 mained lying on the gauze, thus coming in the closest possible contact 

 with the water underneath. The remainder of the roe I kept in a ves- 

 sel in my room, changing the water several times every day. Later I 

 took some eggs of both portions every day and examined them under 

 the microscope, returning them again to the two vessels. The result 

 was as follows: 



At the first examination a faint pulsating motion could be observed 

 in several eggs, but no separate organ whence this motion originated 

 could be noticed. The general color of the young was light gray, with 

 numerous sharply defined streaks, patches, and points of a bright red 

 color. The umbilical sac, of a dark green color, took up the fore part 

 of the body, and had a deep indentation along the line of the back. 

 The eyes were large, dark blue, and motionless. There were indica- 

 tions of feet and feelers. The animal lay curled up in the egg, the 

 distinctly split tail passing between the eyes. Later it was noticed 

 that as the development progressed the umbilical sac decreased in 

 size, while the red color spread more and more. The pulsating motion 

 also increased, the center of this motion appearing to be in the hinder- 

 most portion of the fore part of the body. On July 17, nine days after 

 the roe had been taken from the mother lobster, the shells began to 

 burst, and I deemed my task accomplished ; but unfortunately the 

 principal difficulties began at this time. As I stated before, I had sus- 

 pended the glass with the eggs in the sea, but I made the grave mis- 

 take of suspending it over a grassy bottom instead of a rocky bottom, 

 which is the proper place for young lobsters. The consequence was 

 that a large number of all kinds of small animals gathered under the 

 glass and penetrated through the gauze covering to the eggs inside 

 the glass, where they created considerable disturbance. Several times 

 1 was obliged to take up the glass and clean the eggs; but as none of 

 them appeared to suffer, I determined to carry my experiment to the 

 end without changing the location of the eggs. When the young had 

 left the outer protecting shell the conditions were changed, however, 

 and the small animals, which heretofore had been quite harmless, de- 

 stroyed one young lobster after the other, until on July 20 1 gave up 

 all hope of getting a single one beyond the first change of skiD, and 

 therefore placed all that remained in glycerine. 



Thus far, however, the result was satisfactory, as my opinion that lob- 

 si cr eggs can be developed after they have been taken from the mother 

 lobster was completely confirmed ; and I have every reason to believe 



