THE ANIMAL LIFE OF THE GROUP. 495 



dorsal surface brownish straw coloi', varied with lighter, the ventral surface 

 lighter than the back. The species may or may not have two rows of doi-sal 

 spots. 



A curious and striking worm-like sea-cucumber-'^ is common at I'l'arl 

 Harbor, Kaneohe Bay, and at other points in similar places in the shallow 

 water on sandy and coral bottoms. Large specimens ai-e two or tliice feet in 

 length and an inch and a half in diameter. They vary greatly in coloration, 

 but are usually reddish-orange spotted with brown, the brown forming mot- 

 tlings and irregular bands. They have fifteen or more greenish tentacles an 

 inch or more in length. These animals may be seen by the hundreds in favor- 

 able localities at certain seasons, as they slowly creep about in the algai on the 

 bottom, in shallow quiet water. On being lifted to the surface they completely 

 collapse, as the water which fills the entire animal runs out. Icaviue only the 

 thin contracted bladder-like skin. 



Another very common variegated olive-brown species,-" varied with 

 whitish circles and blotches over the back, takes little care to conceal itself 

 during the day and is quite plentiful, usually in lava rock pools. A fair-sized, 

 dark-greenish species -^ mottled with dark brownish-green is also quite com- 

 mon, especially in the large tide pools on the outer edge of the reef near 

 Honolulu. 



The food of most sea-cucumbers consists of minute particles of organic 

 matter extracted from the sand and mud, taken into the alimentary canal. 

 The species mentioned above as common in Pearl Harbor may be seen in the 

 process of feeding. The plume-like tentacles round the mouth are stretched to 

 their full length. When they have gathered sufficient food particles from the 

 water they are alternately curved round and drawn over the mouth aiul tlie 

 food-charged water forced into the central mouth opening. 



The tube-feet, when present, are the organs of locomotion; l)y them the 

 animal is pulled along on its ventral surface. Several of the species, but 

 especially the loli koko, have a disgusting habit, when disturbed, of exuding a 

 mass of long white sticky fibers that adhere tenaciously to any object, and in 

 which the enemies of the animals are entangled. These thi-eads are i»ai-t of 

 the respiratory apparatus known as the gill tree, but the threads themselves 

 are termed Cuvierian organs. When the loli becomes excessively ii-ritated it 

 contracts the muscles of the body wall to such an extent that the thin wall of 

 the intestine is ruptured and a portion of the long, coiled intestine is pushed 

 out. The animal is only temporarily inconvenienced by this experience, how- 

 ever, as in a short time, after a bi'ief period of (luiescence, nn1ui-c r.M'iirnishcs it 

 with an entire new set of digestive organs. 



CRiNoms. 



While the beautiful and rare sea-lilies or Crinoids ai-e never found on the 

 reef, it is a matter of general interest to know that they belong in the great 



-» Opheodesoma si)ert(ih!h'S. -' Actiitophi/ffa maiiritkiua. =" Stichopiia tropiralix. 



