166 STAR-FISHES. 



back as of no value, is the Sea- Mouse, or Aphrodita 

 (Halithea) aculeata, which is frequently met with in 

 dredging over muddy ground. The body of this crea- 

 ture is oval, three or four inches in length, or sometimes 

 more, soft, dull grey, clothed with a fine silky substance 

 on the back, and thinly covered with small hairs which 

 reflect rainbow colours. The sides are broadly margined 

 with several rows of stiff purple spines, among which 

 are long silky hairs half an inch to an inch in length, 

 of metallic lustre, and reflecting the most brilliant pris- 

 matic colours. Oranges and greens of the richest tints 

 are the most abundant. Under the silky hairs of the 

 back are concealed fifteen pairs of scaly plates, one of 

 which is affixed to each ring of the body, and covers 

 over the branchial organs or gills. The under surface 

 is smooth, transversely divided into about forty rings 

 or segments. Each segment is produced at the margin 

 into a short fleshy lobe or oar-like body, armed with a 

 triple row of stiff spines. These oars, or feet (for they 

 answer partly the purposes of swimming, partly those of 

 crawling), may be contracted at the will of the animal 

 into conical lumps, and the spines may be wholly with- 

 drawn, each within its proper sheath. The spines are 

 curious microscopic weapons, each armed with barbed 

 teeth like those of a fish-spear, capable of inflicting a 

 severe wound on any soft body. 



No one can have thrown down the dredge many times, 

 on almost any sort of ground, and failed to bring up one 

 or other of the various animals called Star-fishes, whoso 

 name sufficiently indicates their form. Sometimes the 

 dredge comes up literally filled with these creatures, 



