A Contribution to the Geologic History of the Floridiaii Plateau. 115 



List of Localities jrom which Bottom Samples were Obtained. 

 (See plate 2, localities platted on the map.) 



Spec- 

 imen 

 No. 



13 

 14 

 IS 

 16 

 17 

 ig 



23 



24 

 25 

 26 

 27 

 28 

 29 

 30 

 31 

 32 

 33 

 34 

 35 

 36 

 37 

 38 

 39 



43 

 44 

 45 



46 

 47 



Locality. 



Junction of the two canals off mouth of Miami River 



Oolite from dredged canal to main ship channel in Biscayne Bay 



Midway between main ship channel and West Point, Key Biscayne, between buoys 



7 and 4 



Northern end of Key Biscayne. Bear Cut, Biscayne Bay 



Opposite West Point. Key Biscayne, Biscayne Bay 



Off eastern shore of Cat Key, south of passage between it and Gun Key (Bahamas) . 

 Off eastern shore of Gun Key, north of passage between it and Cat Key (Bahamas) . 



Calcareous sand from shore, above tide, eastern face of Gun Key (Bahamas) 



Calcareous beach sand, western face of Cat Key (Bahamas) 



Mainland north side of New Cut. Biscayne Bay 



North side of Norris Cut between Biscayne Bay and ocean 



Northeastern corner of Key Biscayne 



South of eastern end of Featherbed Bank 



Lower Biscayne Bay, deepest portion, southwest of Sands Cut 



West of Rubicon Key, off mouth of Ceesar Creek, lower end of Biscayne Bay 



o . 5 mile west of inner end of Caesar Creek, lower end of Biscayne Bay 



Off eastern end, western side of Elliott Key, 50 feet offshore 



Hawk Channel, off mouth of Broad Creek, 2 miles offshore 



.5 mile east of mouth of Angelfish Creek 



Northern end of Card Sound, inner end of Broad Creek 



Card Sound, west of Pumpkin Key, about 200 feet offshore 



Card Sound, southwestern end, 0.5 mile west of Key Largo, and 0.5 mile north of 



spur at lower end of the Sound 



Steamboat Creek, between Card and Barnes sounds 



Barnes Sound, near mouth of Steamboat Creek 



Barnes Sound, center of the Sound 



Blackwater Sound, upper end, off mouth of Jewfish Creek 



Blackwater Sound, 0.5 mile northeast of Bush Point 



Lower end of Hoodoo Sound 



Bay of Florida, entrance from Hoodoo Sound 



Bay of Florida, shoal, 2 miles northeast of Pigeon Key 



The material composing Pigeon Key 



Off inner end of Tavemier Creek 



Shoal southwest of Tavemier Creek about a mile off Long Island 



On Line between McGinty and Torrey keys 



1 mile northwest of Shell Key 



Southwestern end of cut across the bank south of Bowlegs Key 



2.25 niiles northwest of upper end of Long Key 



I mile west of north of western end of Long Key 



1.25 miles north and east of end of Grassy Key 



I mile N. N. E. of Bamboo Key 



0.75 mile north of eastern end of Stirrup Keys 



I mile northeast of the western end of Key Vaca 



o-S mile S. E. of Porpoise Key 



0.25 mile W. N. W. of northern end of No Name Key 



Middle of channel between No Name and Big Pine keys opposite middle of No 



Name Key 



Eastern shore of No Name Key, opposite middle of island, 100 to 200 feet offshore. , 

 0.7s mile north of Bahia Honda Key 



Depth. 



Feet. 



13 

 9 



About 12 



About 8 



9 



2 to 4 



18 



12 



About 9 



About 10 



12 

 About 12 



9 

 About 6 



6 

 9 



7 

 6 

 6 

 12 

 9 

 9 

 6 

 4 

 9 



9 

 ».5 



BISCAYNE BAY. 



From the vicinity and bottom of this bay thirteen samples, including 

 a few beach specimens and one off the northeast corner of Key Biscayne, 

 were obtained. These specimens are Nos. i to 5 and 10 to 17 of the list. 



Specimen No. 2 and some dredged material obtained in digging the 

 canal from Miami to New Cut, which crosses the southern end of the cape 

 east of Miami, show that the Miami oolite extends beneath the northern 

 end of Biscayne Bay and at least partially forms its floor. 



Specimens collected on the north side of New Cut (No. 10) and on 

 the north side of Norris Cut (No. 11) are composed of calcareous and 

 siliceous constituents. There is at both localities a considerable amount 

 of fine quartz sand. 



Specimen No. 4, which comes from the northern end of Key Bis- 

 cayne, Bear Cut, contains an abundance of quartz mixed with shell 



