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after they had been soaking for a month in the hatching-boxes: He thinks that in constructing these boxes pine would be preferable to wood; and it would seem that if wood is the best material some kind other than pine—such as plain, or timber from which the sap had been extracted—might be chosen with advantage.

It seems to be generally understood that a large abatement must be made on every shipment on account of unfecundated ova. The proportion of such has been very large in some shipments. In that by the Norfolk, for example, which took 80,000 ova on board (Tasmanian Rep., 1864), out of 30,000 ova apparently healthy Mr. Ramsbottom estimated the number unfecundated at 16,000.

In the shipment of 204,000 by the Lincolnshire (Tasmanian Rep., 1866), out of about 40,000 apparently healthy it was estimated that about 80,000 ova were barren.

Mr. Buckland says (to Agent-General, 30th Jan., ’73) “that unless the fish are properly manipulated a large number of the eggs will prove to be blind.” But this will scarcely account for the large proportion of blind eggs. It is not unlikely that other causes may operate more effectively than the task of mechanical dexterity in handling the fish.

The amount of ova taken from individual spawners at one time, and the period of the season at which the fish are stripped, may have some connection with the barrenness of so many ova, for it may be assumed that of the ova taken from any spawner those alone that are mature will be susceptible of fecundation. Seeing that large fish continue on the spawning bed for a week or longer it is probable that the ova gradually mature, then, and are not all ready for exclusion at the beginning of that period. If this should be so, then if all or nearly all her ova happened to be taken from any fish at one time some would be immature, and necessarily prove infertile.

Mr. Buist remarks in his report, 1864, that Mr. R. Ramsbottom, when obtaining the ova, that were first placed in the hatching boxes at Stormontfield, “with great knowledge and tact selected the fish that were fully ripe, selecting the eggs so successfully that apparently not one in forty has been addled.”

Into the question of extremes or alternations of temperature as causes of failure the Trustees do not enter, as the data before them at present will scarcely justify an expression of opinion.

The Trustees refer to these points suggestively, having no doubt that due weight will be given to each when the next shipment is under consideration.

The shipment of salmon ova by the Durham has arrived in a condition such as to justify the hope that it will be not less successful than any previous one to this hemisphere. In the view of a large number of fry being reared the Trustees would remind the Government of the recommendation of the late Dr. Gray (New Zealand app. House of Representatives, 1872, G. 26), to place the young fry in one or more “subalpine” streams, in small rather than in large ones, as they would have fewer enemies and be less disturbed. The experiments that were made in 1868 on the temperature of New Zealand waters show, as Dr. Hector has remarked (app. House of Representatives, 1864, D. 2), that only the rivers flowing south into or near Foveaux’s Straits fulfil what is believed to be a necessary condition to the successful acclimatisation of salmon, namely—giving an average temperature under 59 degrees, the average temperature of the sea in the Strait (52 degrees) being also favourable. Taking into account the character of the waters, of the affluents, and of the estuaries of the various rivers flowing into the sea into or near Foveaux Straits the Trustees have agreed to suggest that of the fry reared from the salmon ova shipped by the Durham three-fifths should be placed in one of the affluents of the river Oreti, and of the rest two-thirds in the Aparima and one-third in the Wyndham. All these rivers contain abundance of food in the form of water-fleas, snails, &c., while shrimps and echini, the spawn of which is supposed to be a favourite food, abound in the sea, and a rapid growth of the fish may be confidently anticipated.

Instances of remarkably rapid growth have occurred in the ponds, where some of the brown trout weighed as yearlings to the Makarewa River were found to weigh nearly a pound. Many of them, at seven months old, have been estimated by the Curator, and some proved to weigh 8 or 9 lbs.

The Trustees wish to direct the attention of the Government to the urgent recommendation of Mr. Buckland in the letter above quoted to the following effect—“At the end of the second year build a linsing weir right across the river to test at a very slight expense whether the salmon really come back or not.”

The Trustees recommend that his Excellency the Governor be advised to prohibit, under the provisions of the “Salmon and Trout Act, 1867,” the use—for a time—of nets or engines of any kind to capture fish in the waters, salt or fresh, of any rivers in which salmon have been planted.

And, finally, the Trustees earnestly urge the passing of an Act of Parliament to prohibit all fixed nets or engines for the capture of fish in New Zealand waters.

April, 1876.

Postscript.—In the end of 1875 the Provincial Government of Otago, in concert with the General Government, ordered a shipment of salmon ova to be sent by steamer to Melbourne, and accordingly they were packed in the steamer Durham. She sailed from England on 2nd January, 1876. The ova coming to New Zealand (90,000) were at Melbourne transhipped to the intercolonial steamer coming to the “Bruce,” landed there (with the exception of a few boxes sent to Canterbury), and placed in the hatching boxes on 1st April, thus these ova, brought all the way from Britain by steamers, were placed in the hatching boxes sixty-nine (69) days after having been taken from the parent fish, and, as near as can now be ascertained, eighty-seven (87) days after having been taken from the parent fish.

It was observed that in most—if nearly all—of the boxes the moss was fresh and green; rather closely packed and compressed in those places near the floor of the ice-house. All the moss tasted of turpentine more or less strongly.

Of the ova that came to Southland from 25,000 to 30,000 were apparently healthy, and of these it appeared that about two-thirds were not fecundated.

The hatching is now in progress, and for the present the Curator is unwilling to say anything more definite than an expression of his confident anticipation that this will prove a more successful shipment than that by the Lincolnshire.

The Trustees believe that the mode adopted in this instance of bringing the eggs from Britain by steamers is that which is most likely to effect the successful acclimatisation of salmon in New Zealand—an object which would probably be secured by one other successful shipment, and they trust that arrangements will be made for another shipment in December.

JAS. A. MENZIES,
Chairman of Trustees.

May, 1876.

DISTRIBUTION OF FRY FROM SOUTHLAND PONDS:

1 Salmon Fry, 1874: To Aparima Pond, 96 fish. Carried into Aparima River in June, 1875.