256 BULLETIN 103, UNITED STATES NATIONAL MUSEUM. 



Elevation 80 feet. Prospect, St. James. 

 Stephanocoenia intersepta (Esper). 

 Orbicella annularis (Ellis and Solander). 

 Maeandra labyrinihiformis (Linnaeus). 

 Acropora muricata (Linnaeus) s. s. (as pebbles). 

 Elevation 70 feet. Grazettes, St. Michael. 

 Stephanocoenia intersepta (Esper). 

 Orbicella annularis (Ellis and Solander). 

 Maeandra labyrinthiformis (Linnaeus). 

 Siderastrea siderea (Ellis and Solander). 

 Elevation 40 feet. Sandy Lane, St. James. 

 Orbicella annularis (Ellis and Solander). 

 Maeandra labyrinthiformis (Linnaeus). 

 Elevation 40 feet. Colleton, St. Lucy Parish. 



Maeandra strigosa (Dana). 

 Elevation 20 feet. Black Rock. 



Acropora muricata (Linnaeus) s. s. 

 Just how much of Pleistocene time is represented by this collection 

 I can not say, but it is certainly a considerable part of it. 



Mr. O. E. Meinzer, in the vicinity of Guantanamo Bay, Cuba, ob- 

 tained living species of reef corals on Pleistocene terraces between 400 

 and 500 feet, at 275 feet, 200 feet, 125 feet, and 50 feet above sea level. 

 It is unfortunate that Daly should have attempted to account for 

 the disappearance in the West Indies of so large a percentage of genera 

 that now persist in the Indo-Pacific by appeal to the lowering of the 

 temperature in the western Atlantic Ocean through Pleistocene glaci- 

 ation. In a recently published paper 1 , as well as the present one, I 

 have shown that the genera had disappeared previous to Pliocene time. 

 It is at present my opinion that not enough is known regarding the 

 effect of lowering of marine temperature during glaciation to serve 

 as a basis for very strong arguments for or against the validity of the 

 Glacial-control hypothesis. 



VALLEY-IN-V ALLEY ARRANGEMENT AND CLIFFED SPURS. 



Professor Davis says in his Shaler Memorial study of coral reefs : 



Furthermore, if the embayments of a central island within a barrier reef result from 

 the drowning of valleys that were eroded with respect to lowered sea level of a relatively 

 short glacial period, then each valley must be entrenched in the floor of a preglacial 

 valley; and above the head of each embay ment resulting from the drowning of a 

 new-cut valley, there should be a "valley-in- valley" landscape, unless the pre- 

 glacial valley was so young and narrow that its sides were undercut and destroyed by 

 the deepening and widening of the glacial valley. 2 



1 Vaughan, T. W., The reef-coral fauna of Carrizo Creek, Imperial County, California, and its significance, 

 U. S. Geol. Surv. Prof. Pap. 98-T, p. 366, 1917. 



2 Amer. Journ. Sci., ser. 4, vol. 35, p. 240, 1915 



