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PAPERS RELATIVE TO THE INTRODUCTION

England in the " Celestial Queen." Should the General Government at any time desire to avail itself •f these ponds for tho hatching of ova, there will be no objection on the part of the Provincial Government to take charge of the ova, and to conduct the operations free of cost. I may observe that should our operations at the Waiwera Ponds prove successful, there is no reason why the whole of tho New Zealand rivers should not be supplied with salmon from thence in the «ourse of a few years. I have, &c., James Macandrew, The Hon. tho Colonial Secretary, Wellington. Superintendent.

No. 12. Report by Dr. Hector on the Temperature of the Sea and Rivers in and about New Zealand (No. 45-68 A Geological Survey Office, Sir,— Wellington, 30th July, 1868. I have the honor to forward for Mr. Stafford's information the results of the observations for determining the temperature of the sea and rivers in and about New Zealand, with the view to the introduction of salmon as suggested in my Memorandum of the 23rd December last. These observations will have to be continued for a much longer period before reliable deductions can be made, but already very interesting results are indicated. It appears that the lowest temperature of the sea along the coast is in Foveaux Straits, from the West Cape eastward to Dunedin, where a branch of the great Australian current becomes superficial, and mixes with the great North-east current, giving the low average temperature of 52°. From the West Cape northward the temperature rises rapidly, especially at some distance from land, where it ranges from 64° to 70°. On the East Coast we have a general lowering of the temperature from East Cape, where it is 62°, to 58° at Lyttleton; but in the Bay of Plenty and Hauraki Gulf we find the same temperature as on the West Coast. The inshore observations display such irregularities from local causes that they are not reliable; but the open-sea temperatures are very regular. The temperatures of the running streams show that, .as the best authorities consider that the maximum average temperature for the salmon should not exceed 50°, several of the rivers of the South are suitable for their introduction. The thermometers used for taking those observations wore carefully compared with a standard at this office, and the index errors computed. The instruments were then forwarded in sets to the Provincial Government of each Province, and to the Marine Department, by whom they were distributed to properly qualified observers in various districts wherever it was considered advisable. Tables of observations have been received from many of these; but some districts, where there are important rivers, and even whole Provinces, are still unrepresented. Those which have come to hand have been carefully compiled, and the condensed results are shown in the appended tables and Abstract. In examining this Abstract, it must be borne in mind that the number of observations in some localities— as for instance the rivers in Hawke's Bay —were very few, in some cases even single observations, and at one season only, namely, April, and therefore cannot, of course, be considered an average even for that season. There are, however, some explanatory notes appended by the Provincial Engineer and Surveyor of Hawke's Bay, and by many of the other observers, w r hich will throw more light on this subject. Tho returns have been received in two separate series, embracing the months of March, April, May, and June. They are kept separate in the tables, but are condensed in the Abstract, with, however, the dates appended. In tidal rivers or in an estuary, the time of tide was always noted, and the mean temperature of the ebb and flow ascertained. The returns received are as follows :— Auckland — Rivers Horofiu and "Waikato, at Hamilton: W. M. McColl, Armed Constabulary. River Waikato, at Port Waikato : H. H. Fenton. Hawke's Say — Rivers Tutaekuri, Tukituki, Wairoa, Ngarurora, Mohaka, open sea, and wharf at Napier, &c.: Charles Locke, Chief Surveyor. Sea, at Tiri Tiri Island : . New Plymouth — River Waitara: — . River Urumi: . Harbour at Taranaki: . 'Canterbury — River AVaimakariri: . River Avon: R. L. Holmes, Meteorological Observer. Estuaries of Avon: , Pilot. Little Port Cooper : , Pilot. Akaroa Harbour: Mr. Townsend, District Surveyor. Otago — Tairoa Head : , Lighthouse-keeper. ■ Southland — Estuary of Jacob's River: John Sale, Pilot. Mataura River (at the Falls) : Hugh Cameron. Mataura River (at Aralussa) : A. McNeill. Omutu River : -— -. Waiau River : R. W. Aitkin. Purrapurrakino: — . Orawia and Mosley : B. H. Reinecker.