THE MUSEUM. 



247 



Lobster Hatching at the Woods 



Holl, Mass., Station of the 



U.S. F.C. 



By C. C. Purdum. 



Aside from the numerous interesting 

 geographical pecularities, and facih- 

 ties for the study of natural objects, 

 especially in the absorbingly interest- 

 ing line of marine work, at Wood's 

 Holl, the chief interest centers about 

 the head quarters and fish-hatching 

 station of the United States FishCom- 

 "mission. 



The station consists of the principal 

 buildings: the residence, home of 

 Commissioner McDonald and corps of 

 assistants during the summer months, 

 a large power house by which is run 

 the dynamo supplying the station with 

 electricity. In this building is also the 

 heavy pump which keep a constant 

 stream of salt water passing through 

 the aquaria, etc. 



But the most interesting and in- 

 structive part of the station, by far, is 

 the labratory and fish-hatching house, 

 in which as its name implies, are con- 

 ducted the investigation and hatching 

 operations, together with the extensive 

 marine collection. 



The hatching room takes up the 

 greater part of the ground floor and is 

 supplied with an abundance of pipes, 

 etc., for the conveyance of the water 

 used in the hatching process. 



Situated along the walks are the 

 numerous "hatching boxes" for the 

 hatching of the young cod fish — but of 

 this in a later paper — and which dur- 

 ing the lobster hatching season con- 

 tain the "hatching jars" for the lob- 

 ster eggs. 



The eggs are deposited by the fe- 

 male about the ist to the loth or i 5th 

 of August and are held close to the 



wider surface of the tail, at the junc- 

 tion of the bony plates, by a gelatin- 

 ous substance. 



After being deposited in their situa- 

 tion they remain and do not develop 

 at all until about the middle of March, 

 when they begin to show some devel- 

 opment and then the process goes on 

 quite rapidly. 



Among the "tender morsels" prized 

 by some fishes for a meal (and especi- 

 ally the common Tantoy {Tantoga- 

 onitiis) and common eel [Aiiguilla 

 vulgaris) the eggs of the lobster form 

 a prominent part. The eels get be- 

 low the lobster and by their move- 

 ments detach the eggs and then de- 

 vour them. This causes, of course, a 

 great diminuition in the number of 

 lobsters, and to prevent it the Govern- 

 ment has instituted the above enter- 

 prize. 



The process is as follows: About 

 the middle of March all the ""^gg lob- 

 sters" that can be procured are taken. 

 The eggs are gently removed and the 

 eggs from three lobsters, viz about 

 24,000 placed in the small jars which 

 is supplied with water through a tube. 

 When the water has risen to the proper 

 level the excess is carried off by a si- 

 phon tube into the large jar which is 

 covered by a fine netting or cheesecloth 

 through which the overflow of water 

 escapes when the jar becomes filled. 



When the eggs are placed in the 

 small jar they are constantly kept in 

 motion by the current of water flowing 

 in and out of the tubes but being 

 much heavier than the water, they re- 

 main at the bottom of the jar. 



As already stated, the development 

 of the eggs goes on quite rapidly when 

 once started, so that by the end of 

 four weeks after their introduction to 



