BULLETIN 59, UNITED STATES NATIONAL MUSEUM. 7 



under (litJ(>reiit physical conditions, would throw lijiht on the influence exerted hv 

 the environment. Numerous t'rii<jnientarv .studies of this kind have Iteen niad(>. but 

 none has been thoroughly done. A.s nuicli information obtained in this wav. as i.s 

 po.ssible, is given in the present memoir. 



2. Tyi. nature 1)1/ en'perlnunt. — By i)lanting attached young under the same physical 

 conditions gametic variation could be observed. By transphmting specimens from one 

 area to another, or by planting the young of a given colony undei- different physical 

 condition.s, the effect of environment could be studied. 



'6. Under artljicidl conditimus. — As corals can be grown in aijuaria, inimerous 

 experiments on both gametic and vegetative variation are po.ssible. The l)ehavior 

 with reference to at least seven factors can bo studied: Food supply, heat, light, 

 character of bottom, strength of current, degree of salinity of the water, vai'ious 

 kinds of impurities in the water. Even the influence of pressui-e might be studied. 



The study of variation in nature should go more or less hand in hand with the 

 experimental work. It is to be hoped tliat studies of the kind here outlined will be 

 undertaken by some of our marine biological stations, and that other stations that 

 can undertake such work will lie estal)lished. for until these studies are made it will 

 not b(^ jiossilile to understand vai'iation in the Madrcporaria. Until vai'iation is under- 

 stood the systematic work nuist be more or less unreliable; and until more is known 

 concerning the physiology of corals we can not understand the factors that determine 

 their disti'i))ution. 



HISTORY OF SYSTEMATIC WORK ON THE HAWAIIAN MADREPORARIA. 



Comparatively few men have described Madreporarian corals from the Hawaiian 

 Islands, but work on them was begun at a I'ather early date. 



Lesson, in his Illustrations de Zoologie, 1881, desci'ibed and figured J-lniellum 

 pavoniniiiii. 



Dana, in his Zoophj-tes of the United Stat(>s Exploring Ex])edition, I8J:(!, 

 reported the following species: 



Fjiphyllia pavonina (Lesson ). 



Axtriva [Orhict'Ild) ocellinu Dana. 



FaiHjia dentlyera Leuckart. 



Maniipara capitatu Dana. 



PocUlopora cespUonti Dana. 



Pocillopwa hreviarriii'< Lamarck. 



PocUlopora fai>osa Eh ren I »> rg. 



PocillojMra verruc'iMi Lamari k. 



Pocillopo/'a l!<jidata Dana. 



Pocillopora nwaiidriiia Dana. 



PocUlopora pUcata Dana. 



Pocillopora infoniiU Dana. 



PorUex inorda.r Datia. 



Poritca morda.r var. eloiiyata 1 )ana. 



Porites compi'esm Dana. 



Poriieii hihata Dana. 



Alreoponi dtdtdtn (Forskal). 



