Chap. XI.] 



ACALEPELE. 



399 



undisturbed by a ripple, the minute descriptions are 

 rendered perceptible by their beautiful prismatic tint- 

 ing. So great is their transparency that they are only 

 to be distinguished from the water by the return to the 

 eye of the reflected light that glances from their delicate 

 and polished surfaces. Less frequently they are traced 

 by the faint hues of their tiny peduncles, arms, or ten- 

 taculse ; and it has been well observed that they often 

 give the seas in which they abound the appearance of 

 being crowded with flakes of half-melted snow. The 

 larger kinds, when undisturbed in their native haunts, 



PHTSALUS URTICULUS, 



attain to considerable size. A faintly blue medusa, 



