136 THE SEA-SCORPION FAMILY. 



the gurnard is not one of the most prolific of the ' pelagic ' 

 fishes. 



The male organs in such as the sapphirine gurnard, men- 

 tioned by Mr Holt, are proportionally large, so that some 

 resemble females by the distension of the abdomen. 



As regards the spawning-habitat the gurnard often seems to 

 frequent the inshore waters. Mature gurnards are most abun- 

 dant just outside the three-mile limit, though they are also 

 found in the shallower parts of St Andrews Bay and high up 

 the Frith of Forth. The distribution of the pelagic eggs them- 

 selves, as found by surface-netting, agrees with these facts, the 

 eggs of the gurnard and the sprat being found further up the 

 Frith than any other pelagic eggs. In the autumn the ' spent ' 

 fishes appear again to migrate seawards, so that the migratory 

 habit of the gurnard is to some extent the reverse of that of 

 the cod and the haddock. 



One observer states that the gurnard spawns twice every 

 year, once in the winter and once in the summer, but although 

 there is an isolated case of the egg of the gurnard occurring in 

 Moray Frith in January, yet an examination of the females, as 

 above alluded to, gives no indication of spawning taking place 

 twice every twelvemonths. 



The females of this species are considerably larger than the 

 males, a feature in which they agree with the cod and haddock. 

 In the salmon the same occurs, the difference in this case being 

 due to an earlier maturation of the male : whether the difference 

 in comparative size of the two sexes of gurnards is due to the 

 same cause cannot be stated with certainty. 



The egg of this fish (Plate I, fig. 9), which closely resembles 

 that of the red gurnard 1 , is large, being T52 mm. in diameter, 

 with a large ('28 mm.) and conspicuous oil-globule of a smoky or 

 sometimes salmon-hue. It is less delicate in appearance than 

 those of the cod, rockling or flounder. The perivitelline space 

 is often fairly large before the egg is fertilised, but after this 

 process the germ usually swells up and comes in close contiguity 

 with the egg-capsule. 



The period of incubation varies from eight to fourteen days 

 1 J. T. Cunningham, Join: Mar. Rial. Assoc. I. iv. s. p. 11. 



