lo SALT-WATER FISHES 



shingly ground in the neighbourhood of Selsea Bill, on which 

 the thornback, if accurately figured in the plate that accom- 

 panied Dr. Traquair's description, might easily have rested 

 unseen. 



It is generally assumed that the hottest seas, lying under 

 constant sunshine and cloudless skies, produce the most gaily 

 coloured fishes, and this is in the main a sound theory. 

 Although some of our wrasses {Labrus) and gurnards (Trigla) 

 are almost unsurpassed, while, at their best, the opah (Lampris) 

 and dragonet {Callionymtcs) are quite without rivals, it must 

 be granted that Australian seas, for example, give the angler 

 an extraordinary proportion of bright red and golden fishes. 

 The writer, who went to Australian sea-fishing fresh from 

 seasons spent in Cornwall, in the Baltic, and in the Mediter- 

 ranean, well remembers the interest of his first few outings on 

 the coast of New South Wales, where one brilliant fish was 

 swiftly followed by another, the schnapper eclipsed by the 

 nannygai, and both rivalled by the sergeant-baker. What a 

 contrast from the pollack and whiting of Plymouth Sound ! 



It must have occurred to most people who ever gave the 

 matter a thought that the majority of fishes are much darker 

 in colour along the back and sides than underneath. The cod 

 (Gadus) and conger {Conger) illustrate this among round fishes, 

 while in the skates {Raid) and flat-fish {Heterosomatd) there is, 

 as is well known, a still more striking concentration of dark 

 pigment on the upper surface. The object of this is clearly 

 protection, for in the remora {Echeneis), a little fish which 

 clings to sharks and whales with the aid of a sucking-disc on 

 the back of the head, and consequently passes much of its life 

 upside-down, so to speak, it is the back which is white, while 

 the belly is of dark colour. The cause of this restriction of 

 colour to the upper surface is less apparent than its purpose, 

 but it has not unreasonably been attributed to the action of 

 light. In support of this view, indeed, we have important 

 evidence in Mr. Cunningham's interesting experiments in the 



