JUNE JULY 1903. 



A CLOSE inspection of the flowing tide as it swirls around our 

 gratings reveals the presence of myriads of minute globular 

 jellyfishes the cydippe pileus said to be the favourite food 

 of the arctic whale, though one would scarcely expect these 

 bulky cetaceans to thrive or even subsist on such watery 

 diet. Ranging in size from a pin head to a walnut, what 

 a gap each mouthful must make in their numbers. The 

 poddlies themselves are not averse to this form of food, as they 

 are occasionally seen to disgorge them when landed in our door- 

 way. The common jellyfish progresses through the water with 

 a pulsating movement of the entire disc, such movement being 

 termed " pulmonigrade," and somewhat resembles the action of 

 an umbrella being partially opened and closed. The mode of 

 progression in the case of the cydippe is, however, different, 

 and is termed " ciliograde," as the propulsion is effected by 

 means of eight vertical bands of cilia or minute plates over- 

 lapping each other. Each plate having an independent action 

 of its own, the animal can propel itself in any desired direction, 

 or, by resting them against its spherical body, sink to the 

 bottom. In sunshine these animals in their evolutions emit 

 the most beautiful combinations of colour one could imagine, 

 but " you seize the flower, its bloom is shed " scooped up in 

 the hollow of the hand their beauty vanishes, and only a small 

 spat of inert transparent jelly remains. Here at present in 

 the Rock pools one may witness a peculiar phase in the evolu- 

 tion of the jellyfish. Along with many beautiful varieties of 

 marine vegetation, miniature forests of fir trees garnish the 

 bottom of each shallow pool. These liliputian firs, with their 

 branches no thicker than a hair, are but plants in semblance, 

 for here is the opening chapter in the life history of the 

 medusae. Under the lens each fragile shoot is seen to con- 

 sist of multitudes of small discs piled upon each other like so 

 many saucers, each of which will, in due course, detach itself 

 from its neighbour and enter on its new existence as fully 



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