THE EUROPEAN SEAS. 



i5 



endowed Yvdth life. Some, such as the JBeroe cucu- 

 mis, one of the most characteristic of the northern 

 forms, yet having a wide range to the south, 

 although in fewer numbers, are tinged with a 

 charming amethystine blush. This is the " Foun- 

 tain-fish " of the early voyagers to Spitzbergen, 

 who, mistaking the cause of the eight bands of 

 iridescence, gleaming along the sides of its body, 

 fancied they were so many rivulets of lustrous 

 water. Another, the Cydippe (of which the species 

 represented by Scoresby, is probably my Cydippe 

 Flemingii, and not the true pileus). is furnished 

 with two long pinnated filaments lodged in sig- 

 moid cavities, one on each side of its stomach. 

 By these filaments it can moor itself, as well as 

 guide its path through the waters, retracting and 

 expanding them at pleasure, and, when in rapid 

 motion, usually withdrawing one or the other alter- 

 nately. A third kind, the Mnemia (of which 

 Scoresby's figures, pi. xvi. fig. 3 and 5, are most 

 probably imperfect representations), has no fila- 

 ments, and in general contour resembles the Beroe, 

 but dilfers in having its sides developed anteriorly 

 into great flaps, or swimmers, and the possession of 

 four lanceolate tentacula surrounding its mouth, 

 which, like the Beroe, it carries downwards when 

 swimming, whilst the contrary position is customary 

 with Cydippe. These delicate and beautiful Cilio- 

 grada are abundant throughout the Arctic seas, and 

 seem to have attracted the attention of all the 



