1376 THE STORY OF THE UNIVERSE 



erect and elevated; and is incessantly striking the 

 water with them, with a very peculiar jerking ac- 

 tion, now and then vibrating, and, as it has been 

 called, "twiddling" them. These antennae, there- 

 fore, appear to be always on the watch: let the ani- 

 mal be at rest, let it be feeding, no matter, the supe- 

 rior antennae are ever elevated and on constant 

 guard. 



The lengthened and delicate setae with which they 

 are furnished are, moreover, peculiarly adapted to 

 receive and convey the most minute vibratory sensa- 

 tions from the medium in which they are suspended ; 

 and, on the whole, it seems to be satisfactorily settled 

 by Mr. Spence Bate (to whose excellent memoir I 

 am indebted for these explanatory details) that the 

 inner antennae are real ears. 



Having thus taken our crab by the ears, we will 

 endeavor next to tweak his nose. But stay, we must 

 find it first. We turn our horny gentleman up, and 

 in his flat ancient face we certainly discern little sign 

 of a nasal organ. Our friend Mr. Bate must assist 

 us again. He will tell us to look at the outer or lower 

 antennae. We will look accordingly, magnifier in 

 hand, while he makes it clear to us that these are a 

 pair of noses. 



Each of these organs is formed of a stem consisting 

 in general of five joints, and a filament of many mi- 

 nute joints. In the prawn and the lobster all the 

 five joints of the stem are distinct; but in the crab the 

 whole are, as it were, soldered together into a com- 

 pact mass, with difficulty distinguishable into their 

 constituent articulations; while in some species their 



