BICHE DE HER. 295 



suckers became detached, and the creature fell to the 

 bottom of the vessel. The fact of this locomotion of 

 Echinoderms was well known to Pliny, who observes, 

 " sunt echini, quibus spinae pro pedibus." 



The Comatulae are very large and of splendid colours, 

 in the Indian Seas. I have figured one gigantic species, 

 the pinnate arms of which are of the most beautiful 

 green, the oval disc being of a bright yellow. The Coma- 

 tula, which is merely a detached Pentacrinus, and possibly 

 only an adult form of those pedunculated Echinoderms, 

 enjoys a very considerable latitude of motion, and can 

 even raise itself from the bottom, and propel its body 

 through the water by a series of successive jerks, em- 

 ploying the long flexible arms in the same manner as 

 the Argonaut and Octopus. Both Comatulce and Gorgo- 

 nocephali are very difficult to preserve properly, even if 

 they are first steeped in fresh water. 



A species of Holothuria is common on the shores of 

 these islands, of a dark black colour, being covered with 

 a thick stratum of pigment, which stains the fingers 

 purple, when the animal is touched. The original aspect 

 of this " biche de mer " is concealed by granules of sand, 

 which entirely cover the large cylindrical body. Its 

 branchiae are very beautifully firnbriated, and are of a 

 deep purple colour. There is another species of Holo- 

 thuria with a soft brown, tesselated, integument, which, 

 on being touched, after suddenly ejecting the entire con- 

 tents of its sacciform body, including the whole of the 

 viscera and appendages, through the anal orifice, shrivels 

 up, and immediately dies. Another species is of a bril- 

 liant crimson colour, with several rows of bright yellow 



