74 



Part III. — Twenty -first Annual Report 



The Pogge or Armed-Bullhead (Agomis cataphractus). 



Notwithstanding its small size specimens of this species were 

 occasionally taken in the otter-trawl, their capture being doubtless 

 facilitated by their form. Foi-ty-six wei-e taken by the ordinary net 

 in the Moray Firth in January, June, July, October, November, and 

 December, at Bui-ghead Bay, in the Dornoch Firth, near Smith Bank, 

 and particularly off the coast of Caithness. It was also got in 

 Aberdeen Bay in January, June, September, October, November, and 

 December. It was most common in the winter months; of 123 

 specimens seventeen were taken in October, forty-three in November, 

 twenty in December, and thirty-one in January. With regard to its 

 bathymetrical distribution, while it is abundant in sandy shallows, as 

 in the Sol way and in estuaries,* it is sometimes found in deeper water 

 than is generally supposed. In Aberdeen Bay and the Moray Firth 

 the common range of depth in which the hauls were made was from 

 seven to twelve or fifteen fathoms. Off Dunbeath and Lybster, 

 Caithness, it was taken in many hauls in from twenty-two to twenty- 

 seven fathoms, five hauls, with the ordinary net yielding seventeen 

 specimens. One was taken near Smith Bank in 31^ fathoms in June. 

 In the depression off Aberdeen known as the Dog Hole specimens were 

 occasionally taken in the small-meshed net. One was got in 58 fathoms 

 in August, another in seventy fathoms, 12| miles from shore, in 

 November ; another in sixty-eight fathoms, also in November ; another 

 in fifty-seven fathoms in December, and two in fifty-seven fathoms 

 in January. One 104 mm, in length was taken in May twenty-two 

 miles east of Flugga, at the north of the Shetlands, in eighty-five 

 fathoms. During the trawling investigations of the *' Garland " in the 

 Moray Firth twenty-eight specimens were caught in 308 hauls, and 

 all except five were obtained at the outer stations in moderately deep 

 water. 



They were on the other hand found to be very abundant sometimes 

 in the shrimp-net in the Solway Firth, and weie occasionally also 

 taken in the push-net on the beach in Loch Fyne and Aberdeen Bay. 



A considerable number were examined and measured in order to deter- 

 mine the proportions in number and size of the sexes, the rate of growth, 

 the size when maturity is reached, and the period of spawning. Setting 

 aside a few lots in which the sexes were not completely separated 

 throughout, the result shows 467 females and 398 males, the average 

 size being 88-0 mm. for the females and 86' 1 mm. for the males. The 

 excess of females is considerable, that sex amounting to fifty-four per 

 cent, of the total, and the males to nearly forty-six per cent. ; but in 

 sevei-al cases, as in November and March, males were in excess. The 

 greatest disproportion was in October, when 118 females and 74 males 

 were taken, and in December, when the females numbered 127 and the 

 males 90. It is an exception to what appears to be a general rule that 

 in fishes with demersal eggs the males are most numerous. The mean 

 lengths — taking all sizes together — differ very little, viz. by 1*9 mm. 



With regard to the period of reproduction, in a number examined on 

 August 1st one large female l'z2 mm. (4| inches) long had a few large 

 ripe eggs, but the majority were small, as was the case in the other 

 specimens. On 27th September the eggs were small ; in a female of 

 90 mm. the largest measured 0-3 mm. ; one at 56 mm. had eggs up to 

 nearly O'l mm., and in a female of 53 mm. the largest measured 



On one occasion a specimen from the Firth of Forth which I placed in fresh water 

 lived in it for eighteen hours. Vide Ninth Ann. Rep., Part III., p. 250. 



