34 



JELLY-FISHES. 



unfold transparent tendrils, like the tendrils of a vine, which, 

 twining round some foreign object, hold the little bark secure. 

 When no longer wanted, shrinking back into itself, this apparatus 

 vanishes from view, leaving no trace of its existence. 



Minuter forms of these beroes throng the icy seas in countless 

 myriads, and their abundance and exceeding beauty have at- 

 tracted the attention of all northern voyagers. Great shoals of 

 them are there met with, discolouring the water for a vast extent 

 Scoresby observed that the colour of the Greenland Sea varies 

 from ultramarine blue to olive green, and from the purest trans- 

 parency to striking opacity, appearances which are not transitory 

 but permament. The green semi-opaque water mainly owes its 

 singular aspect to minute beroes and infusorial animalcules. It 



is calculated to form one- 

 fourth part of the Green- 

 land seas, between the 

 parallels 74 and 8p. It 

 is liable to alterations in 

 its position, from the ac- 

 tion of currents, but it is 

 always renewed near cer- 

 tain situations from year 

 to year. The whales 

 throng in this opaque 

 water, for to them it is a 

 good wholesome soup, 

 nourishing enough, as may be judged from the following curious 

 calculation : "The number of Medusae," writes Mr. Scoresby, "in 

 the olive green water was found to be immense. They were about 

 one-fourth of an inch asunder. In this proportion a cubic inch 

 of water must contain 64; a cubic foot, 1 10,592 ; a cubic fathom, 

 23,887,872 ; and a cubical mile about 23,888,000,000,000,000 ! 

 From soundings made in the situation where these animals were 

 found, it is probable that the sea is upwards of a mile in depth ; 

 but whether the substances occupy the whole depth is uncertain. 

 Provided, however, the depth to which they extend be but two 

 hundred and fifty fathoms, the above immense number of one 

 species may occur in a space two miles square. It may give a 

 better conception of the amount of Medusse in this extent if we 

 calculate the length of time that would be requisite with a certain 

 number of persons for counting this number. Allowing that one 

 person could count a million in seven days, which is barely pos- 



FIG. 28. FOOD OF THE WHALE. 

 i. Limacina helicina; 2, 3, 4. Medusa; 5. Clio borealis. 



