270 ME. A. E. HUKT ON THE INFLUENCE OF 



The special contrivances by which shallow-water fishes elude 

 w^ave-currents are similar to those that obtain in the cases of 

 the mollusks, echinoderms, and crustaceans already referred to, 

 although, as the fishes are more active, they have not to depend 

 so much on a passive resistance. The fish elude the waves either 

 by attaching themselves to fixed objects, by hiding under stones, 

 by burrowing in the bottom, or by lying quiet whilst the alternate 

 wave-currents cover them with sand. 



The burrowing-habits of the sand-lannce, Ammodytes lancea, 

 are well known. Frequenting, as these fish do, shallow water, 

 and even burrowing in tidal strands where the waves have the 

 greatest power, they could scarcely successfully encounter the 

 broken water in the shallows if exposed to its violence, and 

 unable to take refuge in the sand. 



Another well-known and remarkable fish is the two-spotted 

 sucker {Lepidog aster himacidatus) , which has the power of attach- 

 ing itself firmly to fixed objects by means of its ventral fins. 

 The special defence of this species against wave-currents is per- 

 fect, so long as it can find some immovable object to which to 

 attach itself *. 



Perhaps of all marine fishes the most interesting in their con- 

 nexion with wave-action are the flat-fishes. They seem to have 

 changed their original forms and habits for the purpose of being 

 able to live in shallow waters agitated by waves ; for it is 

 well known that at first they swim vertically in the orthodox 

 fashion. 



All who have dredged for shrimps near the shore well know 

 how abundant are the little soles, plaice, and dabs, from the size 

 of a shilling upwards, that live on the same ground as do the 

 shrimps, and have to conform to the same outward circumstances. 

 If any of these little fish be placed in a vessel of sea-water with 



* Note. — A specimen dredged in the gaping valves of a Pecten on July 5, 1884, 

 stuck to its refuge whilst being dragged along the sea-bottom, hauled to the sur- 

 face, and discharged with a dredgef ul of dead shells on the boat's deck. This fish, 

 when turned out of its shell in a small aquarium, would, on the water being 

 rocked, manifest great anxiety to get back again. During a residence of more 

 than a month in captivity it varied greatly in colour, from a decided red to a 

 shade so pale as to make it an inconspicuous object when attached to the white 

 interior of a Pecten-valve. Another specimen, dredged with algse- on rocky 

 ground on July 20, was of an olive-brown colour. These fish are good examples 

 of the protection against wave-currents afforded by form, and of the protection 

 against animate foes afforded by colour. — A. E.. H. 



