TOE LOBSTER FISHERY. 737 



making experiments whether it would not be possible to protect the tender young of the lobster 

 by hatching them iu boxes or small basins, where they could find a place of refuge till they 

 were so far developed as to take care of themselves. As these first experiments seemed to augur 

 well, they received at their request, aid from the Royal Society for the Promotion of the Indus- 

 tries of Norway (Kgl. Selskab for Norges Vel.) to enable them to continue their experiments in 

 1874. 



u For this purpose, they inclosed a sheet of water by building a strong wall at each end of a 

 sound, between two small islands in the Veafjord, not far from Kopervig. This sheet of water 

 was about 300 feet long and 30 feet broad ; its bottom consisted partly of rough gravel and partly 

 of rocks stretching along one of the sides, and its average depth was about 5 feet. Five hatching 

 boxes were then procured, of which one was placed in the inclosed water, three at Aakrehavu, 

 and one at Kopervig. These boxes were made of cork, and were 5 feet long and 2 feet deep. 

 Both at the bottom and at the sides there was an opening of one-half inch between the boards, 

 which was covered with strips of fine wire-gauze. The boxes at Aakrehavn were, moreover, fur- 

 nished with a light roof, which, without excluding the light, prevented the boxes from being filled 

 with fresh water during heavy rains. Only one of these three boxes was used for hatching; the 

 two other ones being used for receiving the young ones as their number became too large for the 

 hatching-boxes, and for making experiments whether the young lobster can be kept outside an 

 inclosed sheet of water, which it might be difficult to procure iu some places. Twenty-two female 

 lobsters, having roe, were bought, of which three were placed in the inclosed sheet of water and 

 nineteen iu the boxes, not all at the same time, however, but by degrees, just as it was possible to 

 procure spawning lobsters. 



"Professor Rasch, president of the section for fisheries in the Royal Society for Furthering the 

 Industries of Norway, made a report to the society on the hatching experiments, accompanied by 

 prepared specimens, showing the development of the young lobster on each day of the first week 

 after the hatching, and during the fourth week. Iu this report he says that, in his opinion, the 

 experiments have been made carefully and skillfully, and that thereby several facts regarding the 

 natural history of the lobster have been made known, which hitherto were either entirely unknown 

 or not sufficiently proved by experiments. These facts are 



"a. That the young lobsters swimming near the surface of the water are killed by violent rain, 

 which was successfully avoided by having the above-mentioned light roofs over the boxes ; 



"6. That the older of the young lobsters, when their claws are developed, in their boxes 

 attack and eat the younger ones which stay near the surface; the possibility of doing this was 

 diminished by having holes in the sides of the boxes large enough to let the larger of the young 

 ones which stay deeper under the water slip out easily ; 



"c. That the female lobsters which have roe under the back part of their body in June will 

 have done hatching in September ; 



"<?. That the hatching from beginning to end occupies a period of about three weeks; 



"e. That the summer-hatching does not begin at the same time every year (in 1873 it began 

 on the 4th of July, and in 1874 between the 17th and 26th of the same month), which undoubtedly 

 depends on the higher and lower temperature of water ; 



"/. That the newly-hatched young of the lobster keep closely together near the surface of 

 the water, and because but little skilled in swimming become an easy prey to their enemies; and, 



"g. That the young lobsters begin to go toward the bottom when about three to four weeks 

 old, and that there they soon assume their retrograde motion. 



"It was also shown that when the young lobsters have so far developed as to seek the bot- 

 SEC v, VOL u 47 



