MONOGKAPH OF THE EXISTING CKINOIDS. 597 



quiet anchorages. It is quite probable that the young of many species display 

 considerable activity for a longer or shorter period between the time the column 

 is discarded and the assumption of the adult habit of life. 



Species found between tide marks. — At King (Padaw) Island, in the Mergui 

 archipelago, Dr. John Anderson collected a dozen examples of Aviphimetra dis- 

 coidea, half of them from mud flats exposed at spring tide. 



Mr. Cyril Crossland found Lampro?netra palmata living between tide marks 

 at Suez. 



On the sand flats on the southern side of Friday Island, Torres Strait, at low 

 tide, Dr. H. L. Clark collected a single specimen of Zygometra punctata. 



Prof. S. J. Hickson told me that at Macassar he was surprised to see comatulids 

 at low tide clinging to the piling of the wharves above the surface of the water. 



Dr. H. L. Clark writes that at Buccoo Bay, Tobago, Tropiometra picta occurs 

 in water from a few inches to several feet in depth at low tide, and that at the 

 lowest tides some individuals are probably out of the water, in part at least, for a 

 short time. 



It is only reasonable to suppose that all the species inhabiting coral reefs or 

 other localities where the water is very shallow at low tide are occasionally left dry. 



Species found on coral reefs. — The following species have been reported by 

 shore collectors from coral reefs: 



Comatella nigra., C . stelligera, C. maculata. 



CapiUaster sentosa, C. multiradiata. 



Comissia littoralis, C. hartvieyeri, C. ignota. 



Comatula pectinata, C . purpurea, C . Solaris. 



Coma-iter novaeguineai. 



Comanthus samoana, C. annulata., C. parvicirra. 



Stephanovietra echinus, S. spicata, S. monacantha, S. indica. 



Liparometra re galls. 



Lamprometra protectus, L. gyges, L. palmata. 



Dichroinetra flageUata, D. afra. 



Cyllo-metra disciformis. 



Colohometra perspinosa. 



OligoTnetrides adeonce. 



Tropiometra afra, T. cannata, T. indica, T. audouini, T. picta. 



Antedon vwroccana, A. diihenii. 



Dorometra nana. 



In addition to these the records of capture of a very considerable additional 

 number make it reasonably certain that they were taken on coral reefs. 



As a general rule the reef-inhabiting species choose more or less protected 

 situations, living on the lower surfaces of rock masses, in the cavities of the coral 

 heads and sometimes of large sponges, or among the branches of the arborescent 

 corals; but certain species provided with strong stout cirri frequently occur cling- 

 ing to gorgonians, hydroids, or bryozoans. 



