REPOKT OF COMMISSIONER OF FISH AND FISHERIES. 159 



termine suitable places for obtaining the spawning iish, the means 

 necessary for securing them in good condition, and the apparatus best 

 adapted to the hatching of the egga. The scientific inquiries were to 

 be directed chiefly towards ascertaining those facts respecting the nat- 

 ural history of the parent flsli and of the embryos which could be turned 

 to practical advantage in the artificial propagation of the species. The 

 work continued until the end of Jidy, 1891, and, therefore, only the pro- 

 gress made during the last half of June belongs appropriately to this 

 report. 



The vicinity of Cape Charles City was found to oft'er good facilities 

 for the work, but breeding fish in suitable condition were very difficult 

 to obtain. By the ordinary methods of capture in the pound nets, the 

 fish are held in captivity over night, and those which do not spawn before 

 morning (they are supposed to be mainly nocturnal spawners) are sub- 

 jected to so much pressure and rough handling when the nets are 

 emptied on the next day that, as a rule, they lose not only what ripe 

 eggs they contain, but also many immature ones. An attempt was 

 made to secure them by means of gill nets, but only a few were so 

 taken, and the nets were almost invariably torn by sharks and gars. 

 It is suggested that several pound nets might be run exclusively for 

 the benefit of the hatching work, in which case they could be hauled at 

 night, and in such a manner as to retain the spawning fish in good con- 

 dition. 



It was ascertained that the ovaries of this species mature slowly and 

 not at the same rate in all parts. Consequently, ova in very diflerent 

 stages of development Avere found in the same fish. The largest num- 

 ber of ripe eggs taken from a single fish at one time was 60,000. The 

 movements of the schools were nmcli influenced by the physical condir 

 tions of the water and atmosphere, but precisely to what extent was not 

 determined. The fry were planted soon after hatching, and it was found 

 impossible to keep them alive in the small compass of an aquarium for 

 more than a week at the most. As young fish, especially alewives, are 

 very abundant at the surface at this season, it is considered that the 

 embryo mackerel stand a poor chance of escaping such enemies Avhile 

 in their earliest and most helpless stages, and it is suggested that some 

 means of confining them along the shore might prove advantageous in 

 case the hatching work should be undertaken upon a large scale. 



The tidal or cod jars Avere employed successfully for this species. 

 The eggs were found to be buoyant in the bay water of ordinary den- 

 sity, but sank and afforded i)oor results if the Avater became too brack- 

 ish. Up to July 1, 1,000,000 fertilized eggs had been taken from 30 

 female fish, producing 360,000 embryos, which were planted in the 

 vicinity of Cape Charles City. The length of time required for hatch- 

 ing after the eggs had been impregnated was about tAventy-four hours. 



