Arthur. — On Fish Culture in New Zealand. 205 



spots ' black and crimson ' were very conspicuous. The females were clear 

 and silvery, like sea trout, and crimson spots were visible, which probably 

 in the summer season would not be discernible on the same individuals. The 

 hook on the lower jaw of the males seems to grow larger and softer during 

 the spawning season in our rivers, just as observed elsewhere. 



As the Water of Leith is a small stream, and the trout taken for stripping 

 are often of great size, lOlbs. to 161bs. in weight, the manager when done 

 with the fish, and on their recovery, has for the last few years returned only 

 the lesser fish to the Leith, the larger ones being removed to the Waikouaiti, 

 Waitati, Silverstream, Waitahuna, Clutha, and Waipahi rivers ; or put them 

 into the" Waihola and Tuakitoto Lakes, and the Tomahawk lagoon. The 

 object of this is to make room in the Leith for the growth of the younger trout. 



Stripping the fish. — A crockery basin or bowl being ready, having a small 

 quantity of pure water in it, the female fish ripe for stripping is removed 

 from the tub wherein she and others have been placed temporarily. The 

 fingers of the left-hand, if a heavy fish, are passed through the gills and 

 the tail is seized by the right. Lifted thus from the tub, so soon as she 

 becomes manageable, the left hand and knees keep her in position over the 

 basin, while the fingers of the right passed gently down her belly from above 

 the ventrals to near the vent, effect the stripping. If the female be very 

 ripe the eggs will flow with little or no pressure from the fingers, but if not, 

 then a certain number only may come away, when she is returned to the 

 lying-in pond at once, and allowed to mature. * When stripped the poor 

 female trout has a very collapsed appearance ; the belly, which before was 

 full and distended, being empty, straight, and doubled in ! On being, 

 however, returned to the pond she soon recovers, very few ever dying from 

 the effects of this artificial spawning. A short time — not more than a minute 

 and a half or two minutes — suffices for handling thus a fish. Next in order, 

 when the basin is full enough (it should not have too many) of eggs, a male 

 is got, and similar handhng with that just described gives the necessary 

 quantity of milt, provided the fish be ripe. The milt from one male we 

 find quite sufficient to impregnate the ova of several females, and that of 

 a young male seems to be as efficient as that of a more mature trout. The 

 milt and eggs are stirred gently with a spoon to ensure thorough contact. 

 The female eggs are of a glossy dark pink colour on passing from the 

 ovaries, but I have noticed a faint yet distinct alteration to a semiopaque 

 and slightly milky tint, on impregnation taking place. I have preserved 

 specimens of unimpregnated and impregnated eggs in glycerine, so as to 

 retain the natural colours, and this difference in certain lights I believe I 

 can still distinguish. 



* Mr. Howard, of Wallacetown ponds, uses a board with netting attached to one side 

 to secure the fish during stripping. 



