Plate XVI. 

 {Top left) By-thc-wind sailor, Velellii. 



Photograph by D. P. Wilson 



{Top r/'ij/if) The sea butterfly, SpirtitclLi. 



Photograph by D. P. Wilson 

 {Bottom) Conib-jellics, I'lcKrohriuhiii pilfiis. 



Photograph by Lennart Nilssoii (from Life in tin- Sea) 



