X. 



OCTOBER 



THE naturalist who has occasion to make a voyage 

 over the warmer regions of the ocean, is continually 

 delighted by the sight of numberless forms of animals, 

 principally of the lower invertebrate classes, which 

 either habitually swim at the surface of the sea, or 

 come thither at intervals to enjoy the stimulus of the 

 atmospheric air. Many of these are exceedingly curious 

 and interesting ; many totally unlike any forms that 

 occur on the shores of temperate countries ; many ele- 

 gant in contour, and adorned with brilliant colours. 

 Perhaps there is scarcely any that takes a stronger hold 

 on the fancy, certainly none is more familiar, than a 

 little thing that he daily marks floating in the sunlit 

 waves, as the ship glides swiftly by, which the sailors 

 tell him is the Portuguese man-of-war. 1 Perhaps a 



1 Physalia pelagica, of which a representation is given in the centre of 

 Plate xxvui. Some naturalists make two or three other species, but I do 

 not think that their distinctive characters can as yet be depended on. 



