PROTECTIVE FEATURES IN YOUNG OF VERTEBRATES. 1 1 7 



which are also most thickly covered with Membranipora. The 

 small fish Antennarius is in the same way coloured weed-colour 

 with white spots. Even a planarian worm is similarly yellow- 

 coloured, and also a mollusc {Scyllaa pelagicd). The white 

 patches in some of the crabs, no doubt, represent also, to some 

 extent, the white shells of barnacles, though these are not very 

 abundant in the weed." Professor Moseley instanced a tunicate, 

 a glassy Salpa of which the nucleus was of a dark red-brown 

 colour in imitation of the tint of the floating sea-weed. 



But many of the vertebrates, especially our common marine 

 fishes, furnish striking instances of protective coloration. The 

 sole in an advanced larval condition is patched in the most 

 grotesque and erratic manner with warm ochreous blotches, and 

 resembles a minute shred of floating weed, for the transparent 

 parts of the fish are invisible. The definite transverse bands of 

 the newly hatched cod and the longitudinal stripes of the late 

 post-larval ling may be persistent traces of ancestral coloration 

 not now of much protective significance; but the post-larval lump- 

 sucker ( Cydoptems), the father-lasher ( Cottus), and other common 

 shore fishes are grotesquely blotched with the most diverse shades 

 of black, brown, green, and yellow, while irregular patches of gleam- 

 ing white may occur on the head or trunk and perfectly mimic 

 fragments of corallines and encrusting polyzoan colonies. The 

 protective coloration of immature and mature animals is, however, 

 a familiar subject, and the object of this short paper is to point 

 out protective structures less familiar and less obvious, and in 

 many instances not hitherto observed or fully described. It is 

 interesting to find that in the highest and lowest vertebrates alike 

 there occur these curious embryonic and larval wrappings, differing 

 so much in structure and origin, but subservient to the same 

 protective purposes. 



