Physalia Pelagica. 237 



been termed the beat, and rounded at the other. Along the 

 highest part of what may be termed the back, forming a kind 

 of ridge, is a crest, which can be elevated or depressed at will, 

 and it is much larger in some specimens than others. This 

 ridge or crest is sulcated and fringed at the edges. The lower 

 part of the vesicle or bladder is of a light blue colour, streaked 

 or veined almost imperceptibly with delicate green pencillings, 

 the crest and beak being of a rich carmine, changing in various 

 lights to a bronzy-green or purple. But these beautiful hues 

 fade very soon when it is taken out of the water, with the ex- 

 ception of those of the long purple tentaculie, which retain 

 their colour till decomposition takes place. 



This singular floating bladder, with its marked crimson 

 ridge, from which purple veinings extend down the sides, 

 might, by a fanciful naturalist, be considered as the primal 

 foreshadowing, or, as he might say, the nebulous origin of the 

 fish form, the dorsal ridge foreshadowing the spine, and the 

 blue veins marking the position for the future ossified radia- 

 tions. The raised crest might represent the dorsal fin, the 

 cartilaginous beak the position of the bony mouth, while the 

 office of the gills and the ventral fins may be represented by 

 the branchias or short tentacles, the air-bladder forming the 

 natural basis of many animals calculated to float in the water. 

 Such a fanciful notion is not altogether extravagant, and in 

 this age of speculative science, some physiologist, wedded to 

 the hypothesis of gradual development, may be found to work 

 out the theory that the Physalidas are what Laplace might have 

 termed the nebulous stage in the gradual creation of fishes. 



It has been said that the Portuguese man-of-war has the 

 power to collapse by the exclusion of a portion of air from the 

 bladder, for the purpose of sinking in the water, as fish do, 

 and that it does, in fact, exercise this power on the approach of 

 storms, when it seeks protection for its delicate structure by 

 sinking to a great depth below the agitated surface. Mr. 

 Bennett, however, positively asserts that it possesses no power 

 of the kind, and that no apparatus can be detected, on the most 

 delicate dissection, by means of which collapse or expansion 

 could be governed. He states that he has seen them, in storms, 

 turned over by the waves, when their great buoyancy causes 

 them to regain their position without effort. He has observed 

 also, in tempestuous weather, that so far from having been able 

 to sink into the ocean depths for protection, they have been cast 

 upon the shore in great numbers, the vesicle still remaining 

 fully expanded. He also found that the air could not be forced 

 out of the bladder except by violently bursting its tough vesi- 

 cular tissue. The long tentacles appeared to Mr. Bennett to 

 consist of a series of globules containing fluid matter, and hav- 



