234 BRITISH FRESHWATER FISHES 



THE THIN-LIPPED GREY MULLET (Mugil capita) 

 (PL XXXIV, Fig. b) has the upper lip still thinner; 

 the maxillaries are exposed when the mouth is 

 closed, although not to the same extent as in the 

 Thick-lipped Mullet, but the rami of the lower jaw 

 are separated by an elliptical area ; the pectoral fin 

 is shorter than in the other species, measuring less 

 than three-fourths of the length of the head, whilst 

 above its axil appears a scale which is more or less 

 elongate and is free except at the base. This is 

 the most widely distributed of our Grey Mullets, 

 extending from Scandinavia to the Cape of Good 

 Hope ; it attains a length of 2 feet. 



The Grey Mullets swim in shoals near the coasts, 

 and especially in the summer-time frequent estuaries, 

 going in and out with the tide, whilst at times they 

 may ascend far beyond tidal limits. Thus Yarrell 

 mentions that in the summer of 1834 Grey Mullets 

 migrated up the Arun in Sussex to 10 miles above 

 Arundel, whilst Thompson records that they have 

 been known to ascend the Lagan at Belfast into 

 the canal, where they have been shut in by the 

 gates and have been seen leaping in the fresh water. 



They are very lively and often sport at the 

 surface ; their food consists mainly of minute shell- 

 fish and of decomposed organic matter which they 

 extract from mud ; their gills are protected from the 

 latter by a sieve-like apparatus formed by the 

 numerous gill-rakers. They are bold and cunning 

 and often escape the fishermen either by leaping 

 over or forcing a way under the nets ; they are 

 sometimes captured by anglers with an artificial fly 

 or with a bait, but as they suck at the latter and 

 eject it immediately they have taken it into their 



