1014 



SCIENCE. 



[N. S. Vol. XIV. No. 365. 



aging results, and it was thought that the estab- 

 lishment of sevei-al stations might result in the 

 discovery of some locality having physical and 

 biological conditions more favorable than those 

 found at the government laboratory. The offi- 

 cers of the stations at Gloucester and Woods 

 Holl and the officers of the Grampus, Fish 

 Hawk and Phalarope cordially cooperated in the 

 work of the special committee, but the expei-i- 

 ments at all the stations excepting that at Wick- 

 ford were discouraging. The lobster fry, even 

 in the cold clear water of the Gulf of Maine, 

 would soon become covered with a chenille-like 

 growth of diatoms and would die, no matter 

 what kind of enclosures were used. 



At Wickford, however, where the Ehode 

 Island Commission had courteously given the 

 use of their floating house-boat, the fry seemed 

 to find a more congenial environment. In what 

 respects the water and the plankton at Wick- 

 ford were more favorable to the fry cannot at 

 the present time be stated ; it was, nevertheless, 

 a fact that the young taken from the hatchery 

 at Woods Holl would quickly perish when con- 

 fined at various localities near Woods Holl, but 

 Avould thrive when placed in the same kind of 

 enclosures at Wickford. The water at Wickford 

 is rather fresh and of high temperature (often 

 ten degrees higher than at Woods Holl). It is 

 charged with vegetable and animal life, and the 

 current is sufficiently strong to assist materially 

 in the aeration of the water in the enclosures. 



Many different devices for enclosures were 

 adopted and tried. Large salt-water ponds, 

 smaller pools, artificial pools made by the build- 

 ing of dikes, enclosures made of wire screen 

 and floated and wire screen and submerged, 

 huge canvas boxes and cars, cars of sci-im 

 floated and anchored at the bottom, glass jars 

 of various sizes, running water in vessels of 

 wood, metal, glass, porcelain and stone, and 

 various rotary devices, all proved efficient 

 agents for the killing rather than for the rearing 

 of lobster fry. 



The only enclosures which gave encouraging 

 results were made out of scrim in the shape of 

 huge bags some sixteen feet in diameter and 

 several feet in depth and so leaded at the bottom 

 that they would rise and fall with the current 

 and agitate the enclosed fry. But the current 



was not sufficient at all times to keep the young 

 lobsters from settling to the bottom, devouring 

 one another and gathering into a confused 

 mass of maimed and struggling individuals. 

 At these times it was necessary for the staff at 

 Wickford to agitate the water artificially, and 

 this was done by the use of paddles. 



To Dr. A. D. Mead, who was the director of 

 the Wickford laboratory, is due the credit of 

 having demonstrated the importance of keeping 

 the young lobsters from the bottom of the 

 enclosure, by either natural or artificial means. 



Under favorable conditions the growth of the 

 young fry is phenomenal. The first molt takes 

 place about six days after the young have left 

 the egg, the second molt some six days later 

 and the third about five days later still. The 

 third molt takes the fry into the fourth stage, 

 when they assume the characters and habits of 

 the adult. Under the most favorable conditions 

 this fourth stage may be reached in nine days 

 from the time the lobsters are taken from the 

 hatching-jars, but under less favorable condi- 

 tions, within the same enclosures, certain indi- 

 viduals may be found in the second stage after 

 a lapse of several weeks. In both structure 

 and habits the young that have reached the 

 fourth or ' lobsterliug ' stage are very different 

 from those of the previous stage. These older 

 individuals (known at the laboratory as ' four- 

 ses ') are provided with pinching-claws, hardened 

 shell and vigorous muscles. They are very 

 active, have a voracious appetite, and are pug- 

 nacious and secretive. 



It is well known that the planting of a few 

 young trout in the fingerling stage will accom- 

 plish much more toward restocking our streams 

 than the planting of many thousand fry, and I 

 think it safe to conclude that the planting of 

 many thousands of lobsters in the ' lobsterling ' 

 stage would do much more toward rehabilitating 

 the waning lobster industry than the planting of 

 many millions of helpless fry as they leave the 

 hatchery. 



No special effort was made in 1900 to treat 

 the fry after they had reached the foui'th stage, 

 but a few were retained. Those of the United 

 States Fish Commission office at Washington 

 have been obliged to endure the more artificial 

 environment of an aquarium. Those at Wick- 



