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Part III. — Twenty-seventh Annual Report 



horizontally. A considerable number of the fry was seen lying on the 

 smooth bottom of the tank. Some were able to rise from the bottom ; 

 others remained there and died. Some of the larvae were curved. When 

 they attempt to rise oft 1 * the bottom, the bend in the body brings them back 

 to their starting place. Meyer noticed that some of the larvae hatched 

 during his experiments at Kiel were also curved. The tank at this time had 

 no water circulation. It had a large body of water. The circulation was 

 dispensed with, as it was feared the fry might be carried away with the 

 outflow. But the still condition of the water resulted in another danger. 

 Next day many of the larvae were floating dead on the surface. They had 

 on swimming upwards become attached to the surface film, and had been 

 unable to free themselves. One larva had its head opaque, while it could still 

 wriggle its tail. A fairly violent wave motion of the water in the tank was 

 necessary to dislodge some of the larvae from the surface. Fry in which the 

 yolk was absorbed also suffered death in this fashion. With a view to 

 prevent this mode of destruction, a small jet of water playing obliquely on the 

 surface was set up, and from time to time the water was strongly agitated. 

 On the sixth day nearly all the fry were dead in the tank ; they lay thickly 

 spread on the bottom. 



The herring fry generally kept, attracted by the light, to the pane next the 

 window. They wriggled up and down over the glass in a lively fashion, 

 stopping now and then over the diatom patches as if browsing (?). When, 

 however, they were examined by means of a lens through the glass front no 

 food was made out in the alimentary canal. Sometimes the fry was observed 

 collected in a shoal along the bottom of the pane ; some were continually 

 rising to sink again. The light seemed to be an irresistible attraction to the 

 fry ; it is therefore possible that a side light is not an advantage in a rearing 

 tank. Amphipods appeared regularly in the tank. They did not get in 

 by the water supply ; they must have come up the drain. They groped 

 their way blindly among the fry collected at the foot of the glass front, but, 

 while scattering them, they were not noticed to catch any of the larvae. In 

 April the amphipods, which were diagnosed by Dr. Scott as Orchestia 

 littorea, were to be found in numbers on the floor of the tank-house and in 

 the engine-house, while outside in the yard they were very common beneath 

 pieces of wood. They made their way up the drain into a perfectly dry 

 tank. They were always removed when they appeared in the rearing tanks. 



In a second tank a layer of sand and gravel was put on the bottom. The 

 surface was thrown into rolls and irregularities with a view to helping the 

 fry to rise off the bottom. The pane next the window was covered with a 

 heavy blind. A gentle agitation of the water was secured by means of a 

 small water-wheel. The sand on the bottom acted as a means for pre- 

 venting the escape of the fry by the outflow. Some time after this tank was 

 set in operation a number of dead fry were seen sunk in the sand next the 

 glass. They had apparently burrowed their way downwards into the sand. 

 This happened at a part of the tank far away from the outflow. 



On April 13 a number of the larvae had the yolk all absorbed. 



The fry from the cooled spawn did just as well in the cooled water as in 

 the uncooled. Three were alive on May 11, but they were very weak. 



The want of suitable food was probably the cause of the failure to rear 

 the fry. 



Meyer succeeded in rearing the fry at Kiel. 



The Transport of Living Adult Herrings. 



Some herrings were sent at the beginning of March from Anstruther to 

 Aberdeen in closed barrels. Most of them arrived alive. In one lot seven 

 out of ten were still able to move about. They had been captured in a 



