42 KECKNT MADKEPOKARIA -K THK HAWAIIAN ISLANDS AND LAY8AN. 



NdUTHWKsr (OAST. 



K,.,-or(is: Twolvo. 7T : four. 7s : IC records: range, 77 to 78°. 



SdiTnwKsT Coast. 

 Records: Six, 79". Toinpcratiirc the samo for each record. 



KaIEIK-\Vm1.. ClIANNKl., IIKTWKEN OaHC A.M) KaUAI LsLANDS. 



Records: Two. 77 : four. 7S : (I records; range. 77 to 78". 

 VKMNITY OK KAKAI ISLAND. 



Records: Three, 75"; six, 7ti ; forty. 77 ; thirty-six. 7s ; two. 7!t-: S7 records; 

 range, 7J to 79'. 



VICINITY OK MODI' MANX", OR BIRD ISLAND. 



Records: Two. 74 ; three, 75-; eighteen, 77 ; thirty-one, 78- eight, 79- : 62 

 records; range. 74 10 79"^. 



FRENCH FKIC.ATE SHOAL. 



Records: Four. 74 : two, 75 ; .seven, 7tl : 13 records; range, 74' to 76°. 



LAYSAN. 



Records: One, 73^; eight, 74 ; twenty-three, 75'^; thirty. 76 ; four. 77: one, 

 78°: 67 records; range, 73' to 78 . 



These records, when considered together, show a total range in the surface 

 temperature of the water from 73 to SO-. The oh.servations were made between 

 March 27 and August 29; tiiey thei-efore are the sununer temperatures. Unfortu- 

 nately data regarding the winter temperatures are not at hand. 



ileef corals, growing practically at the surface of the water. wer(> ol)tained on 

 the .south coast of Molokai. the south coast of Oahu, the north coast of Oahu, and 

 from Laysan. The surface temperature of the south coast of Molokai ranges from 

 73° to 76°; that of the south coast of Oahu from 76 to 77^; that of tlu> north coast 

 of Oahu from 74^^ to 75 '; that of Laysan from 73- to 7S-. There is in the summer 

 time on the coral-reef areas of the Hawaiian Islands a range only of 5^ in the surface 

 temperature of the water. 



These data oti'er nothing new regarding the temperatui'e conditions favorable 

 for the growth of reef corals, Dana, in his Corals and Coral Islands, third edition, 

 having given a satisfactory discussion of the subject. The data here presented 

 rcirai-ding tlie Hawaiian Islands, however, furnish a starting point h>r the present 

 study. According to l);ina. reef corals can endure a range in teiuperature from 

 68° F. to 85'- F.. but the annual mean nnist not be below 7n ; the sununer would be 

 higher. The lowest sununer surface tt>mperature recoi'ded l)y the A/hattoss vfHslS'^. 

 The following .schedule will be adoi)tetl: Species found between 7s- and 73-; 73° and 

 60°; 60° and 50°; 50 and 4D ; 4u- and 30°. 



