SPIDEES AND MTIES. 251 



cles of dust and other extraneous matter which are 

 continually cleaving to them. 



There are Spiders in the sea also. I can show you 

 one which is sufficiently common on the southern 

 chores, sprawling and crawling sluggishly among the 

 filamentous seaweeds and branching flexible zoophytes. 

 Here it is, NympJwn by name. 



Its most prominent characteristic is the excessive 

 slenderness of all its parts, but especially its eight legs, 

 which are exceedingly lengthened, comprising each 

 eight joints, and no thicker than the finest thread. On 

 the other hand, the body is reduced to a minimum ; the 

 abdomen, which in the Spiders and Harvestmen of the 

 land is so bulky as to constitute the chief volume of the 

 animal, is here so minute that you will have some dif- 

 ficulty in finding it at all ; it is, in fact, that tiny atom 

 of a point that projects between the hindmost pair of 

 limbs. The thorax, indeed, is a little more developed ; 

 but even this has scarcely any appreciable breadth or 

 thickness, being scarcely more than the extended line 

 formed by the successive points of origin of the limbs. 



The head, however, is distinct and well furnished. 

 It is crowned with a short column, much as in the Har- 

 vestman, on the summit of which are placed four black 

 eyes, set in square ; these, under the magnifying power 

 which we are applying to them^ gleam like diamonds, 

 the light being highly refracted through them. It is 

 the high refractive power of these eyes, as of those 

 which we have lately been examining, which makes 

 them appear black ; for, as I have explained, they are 

 really transparent lenses, covered with polished cor- 

 nese, and furnished with the other essentials requisite 



