80 LIVING LIGHTS. 



In some of these creatures the luminous property has been 

 observed, — which usually surrounds the entire animal, — a 

 pale light, rendering the object a beautiful one against the 

 dark background of the ocean bottom. It is needless to say 

 that the human eye has not penetrated these vast depths ; 

 but the ingenuity of the scientist has resulted in the invention 

 of means by which the smallest as well as the largest of 

 these strange creatures are dragged from their deep abode. 

 Echinoderms are extremely numerous ; on the Florida reefs 

 we have often found it impossible to wade through consider- 

 able areas, where a kind of sea-urchin having long, slender 

 black spines was so numerous as to pave the entire sea- 

 bottom, and in certain localities in Long Island Sound we 

 have seen the bottom fairly carpeted with star-fishes. It is 

 not surprising, then, that the dredges of the " Challenger," 

 " Porcupine," " Talisman," and other ships fitted out for 

 scientific investigation, often came up loaded to overflow- 

 ing with star-fishes, showing that the deep sea is equally 

 populous with these living stars. 



These deep-sea forms, especially of the genera Asterias and 

 OpMura,^ are remarkable for their brilliancy, even when 

 taken from their native element. When the bottom off the 

 coast of Ireland was dredged by the " Challenger," an extraor- 

 dinary number of luminous star-fishes were brought up from 

 a depth of two-thirds of a mile. Several specimens are 

 most noticeable for their brilliancy ; ^ they appear as if burn- 

 ing internally with heat of great intensity. Even the mud 

 about them was bespangled with luminous specks ; and Sir 

 Wyville Thompson says that in many instances every thing 

 brought up in these waters was luminous. The light of one 

 of the star-fishes was a brilliant green, and seemed to spring 



