Coloration of Marine Animals. 'I'll 



lustre or tlie flesh-tint by no means resembles their sur- 

 roundings, whilst other dwellers in 8an<l, viz. Phijlludoce 

 maculata and Aw ids rosea, are finely coloured. Forms t're- 

 quenting the fissures of rocks or tunnels in calcareous algfc 

 are equally varied in tint, from the sombre <^rey of Trophonia 

 jilumuaaj the deej) green of Kulnlia viriJis, the straw-coloured 

 body and red branehite of AJor^/n/sa, to Lysi'lice with its 

 niadiler-brown anterior end and white collar. Those having 

 finely coloured j)lumes anteriorly, like the Sabellidie, occu|)y 

 tubes, and in few instances are their plumes in harmony with 

 their surroundings. One instance, however, is given by 

 Prof. Semper * of agreement between an allied form {Mi/,ri- 

 cola, one of the Eriographididai) at Port Mahon and a coral 

 (Cladocera). Both the polyps and the funnel of the annelid 

 were of the same chocolate-brown colour, and thus at first 

 sight protective resemblance might have been diagnosed ; but 

 the annelid also occurred in a sponge of a totally different 

 colour and in clefts of rocks where no tint resembled it. When 

 Semper tapjjed the coral the annelids retracted their plumes 

 at once, but the corals remained expanded. There was really 

 no protective resemblance. Dr. Eisig mentions an Eunice 

 parasitic in a sponge of a yellow colour, the annelid being 

 yellow with orange spots, and he considers this an instance of 

 ])rotective coloration^ though Beddard thinks tiie tint arises 

 from feeding on the sponge. As, however, these annelids 

 generally construct a tough parchment-like tube in sponges, 

 the example is dubious. Two annelids, Euphrosyne and 

 Spint/ies, are also partial to yellow sponges, on which they 

 feed and they may be held to be protectively tinted. Some 

 Polynoidaj with mud-covered scales approach the hue of the 

 muddy inner surface of shells dredged from deep water, or the 

 muddy inferior surface of stones between tide-marks. The 

 dorsum under thescales and the free parts of the body posteriorly 

 in others are coloured conspicuously with brown bars, so tliut 

 the case may fairly be claimed as one of protective adaptation. 

 Mahngrenia^ commensalistic on purple urchins, also agrees 

 with Its surroundings, being tinted of a deep jjurple, and tho 

 polynoid in the interior of Euplectelia is more or less trans- 

 lucent. On the other hand, NereilepaSj commensalistic with 

 the hermit-crab in the great whelk, is conspicuously tinted. 



Pelagic annelids, again, are not always colourless, even the 

 Alcio|)idaj having finely coloured eyes. The pelagic stages 

 of Autolytus so common in various seas are often coloureil 

 both green and pink. Little change in the tint of the green 



♦ Fide Beddard. 



