like creatures floating gracefully along, 

 propelled by the rhythmic contractions 

 and expansions of the bell-shaped disk. 

 Now it will be seen to poise itself per- 

 fectly perpendicular in the smooth 

 water, and again it will careen to one 

 side and display its digestive apparatus, 

 suspended from the center. If the crea- 

 ture be viewed in the sunlight it will 

 appear of a beautiful blue color, irides- 

 cent from the flashing rays of the sun. 

 Those who have seen only the un- 

 sightly mass of bluish w'hite jelly, as 

 these animals appear when cast upon 

 the seashore by the storms, can have no 

 idea of their exquisite form and beauty. 

 These animals are found in all quarters 

 of the globe, even in latitudes of ex- 

 treme cold, and no body of salt water 

 of any size is devoid of them. In size 

 they range from a fraction of an inch 

 to over a foot in diameter. Their colors 

 are generally bluish, looking not unlike 

 transparent glass, and occasionally the 

 four radiating canals may be seen 

 through the disk and are colored bright 

 red. Other colors of the Medusae are 

 purple, green and pinkish. In the Por- 

 tuguese Man-of-War, the disk forms a 

 somewhat cylindrical float, with a crenu- 

 lated crest, on the upper surface, and 

 the stomach (or polypite) and tentacles 

 hang down from the under side. These 

 tentacles or stinging feelers are moie 

 numerous in this Medusa than in the 

 majority of species. 



We have described the interesting case 

 of _ the division of labor found in the 

 Millepora, but there is a still more won- 

 derful division of work in the colonial 

 jelly-fishes, called Siphonophora. 



These jelly-fishes are brilliantly col- 

 ored and in many places, in the Medi- 

 terranean Sea for example, they cover 

 the surface over quite an area during 

 certain seasons. These animals have a 

 central fleshy, flexible stem several feet 

 in length, to which are attached many 

 hundred polyps and Medusae, arranged 

 in sets, each set having a different duty 

 to perform. The upper end of the stem 

 is enlarged to form a float and around 

 the stem, just below the float, are ar- 

 ranged a large number of bell-shaped 

 Medusae which alternately open and 

 close, forcing water in and out of their 

 cavities. These are the locomotive or- 



gans and by their pulsations they pro- 

 pel the colony from place to place. From 

 the lower end of this stem a large num- 

 ber of polyp-like structures are sus- 

 pended, divided into sets. One set is 

 pear-shaped, and each polyp contains a 

 long tentacle in which are placed net- 

 tling organs for capturing the food. 

 There are also a large number of long, 

 slender, thread-like organs present, 

 which are special organs of sense. 

 Finally there are the reproductive indi- 

 viduals whose duty it is to produce eggs 

 for the perpetuation of the species. It 

 will thus be seen that this colony of 

 polyps and Medusae correspond to or 

 rather foreshadow the higher and more 

 complex animals, where there is an 

 organ for each function. Animals like 

 these jelly-fishes are said to be poly- 

 morphic. 



The bodies of the jelly-fishes are soft 

 and jelly-like and cannot be well pre- 

 served for study. There is about one 

 per cent of solid matter in their compo- 

 sition, the balance being chiefly water. 

 This is the reason that they become such 

 a shapeless, sticky mass of. jelly when 

 thrown on the sea shore or taken from 

 the water. Should any reader of this 

 article spend the ensuing summer at the 

 sea shore, I would suggest that that one 

 study carefully the jelly-fishes and sea 

 anemones which are sure to be found if 

 carefully searched for. The sea ane- 

 mones will be found clinging to stones 

 in pools left by the receding tide, or per- 

 chance will be discovered attached to the 

 piling of a wharf or bridge. The jelly- 

 fishes come in from the open sea and 

 may be found floating near the shore or 

 imprisoned in a tide pool. The first 

 mentioned animals may be dislodged 

 with a flat-bladed knife pressed between 

 the object of attachment and the animal, 

 but owing to their stinging powers, the 

 Medusae had better be picked up with 

 a small net. These animals may be col- 

 lected in pails filled with salt water and 

 studied alive in marine aquaria. The in- 

 formation gained in this manner will be 

 both interesting and instructive, and the 

 time consumed will be well spent. To 

 realize the true meaning of life, nature 

 must be studied at first hand, when she 

 will yield her choicest secrets to those 

 who will earnestly seek for knowledge. 

 Frank Collins Baker. 



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