26 ANATOMY OF THE SUGAR LOUSE. 



around us, that we are sometimes inclined to believe, as we admire the 

 deepness of its green, that we are upon a liquid meadow, or upon a 

 billiard-table carpet, which could be translucent. In proportion as the 

 vessel becomes distant from the shore, and we reach the high latitudes, 

 where the depth increases more and more, the green tint changes into 

 a blue tint, and in the open sea, the water becomes, at fifty or sixty 

 fathoms, of the finest azure colour. The green shade generally an- 

 nounces danger, or an approach to low coasts ; for along those which 

 are intersected with peaks or mountains, and near which the sound 

 descends to a great extent, the blue azure is observed to appear, and 

 to become much more lively, as the depth becomes more considerable. 

 But this blue, which is ordinarily regarded as one of the characteristics 

 of the ocean, and which is commonly attributed to the manner in 

 which the rays of the sun become decomposed, as they penetrate into 

 the waters, is not, however, exclusively peculiar to it ; every large and 

 deep bed of water has a cast of a similar nature. Deep lakes, which 

 are not salt, especially those among high mountains, are equally affected 

 by the blue azure tint, and this beautiful shade is observed even in the 

 bed of torrents, at the bottom of which, if the water fills a cavity in a 

 rock, the serenity of the heaven produces, in a small degree, the most 

 brilliant effect of colouration. 



ANATOMY OF THE SUGAR-LOUSE. (Lepisma saccharinum, LINNAEUS ) 



BY PROFESSOR TREVIRANUS, OF BREMEN.* 



THE sugar-louse is ranked along with the wood-louse (Oniscus), and 

 water-louse (Asellus aquations), though it is in many particulars not 

 so like the whale-louse (Cyamus ceti, LATREILLE). These insects 

 are similarly filiform, having a structure of numerous small joints, 

 with antennse, tail bristles, and similar eyes placed together so as to 

 shine, which are composed of minute semicircles and faintly shagreened. 

 Like the Onisci, the body is arched above, and composed of numerous 

 small rings. They have only six feet, but in the structure thereof 

 there is not so much resemblance between them and the wood-louse. 

 It must be confessed, however, that the differences are upon the whole 

 no less obvious than these resemblances. 



The body of the sugar-louse is longer and smaller than that of the 

 wood-louse, and is everywhere clothed with small scales. 



* Translated from the German periodical, Vermischtf Schriften Anatomischen, by 

 Edward A. Rennie. 



