130 REPORTS ON INVESTIGATIONS AND PROJECTS. 



sirable to gather large series of specimens of Cerion and associated mollusks 

 for careful laboratory study and experimentation, and this was accordingly 



done. 



Of Cerion alone about 40,000 specimens were gathered from as many 

 localities as were within our reach. From the two places already mentioned, 

 (1) along Kings Road, Bastion Point, northeast side of South Bight, Andros 

 Island, and (2) in the neighborhood of the laboratory, between Sharp Rock 

 Point and Driggs Hill, on the southeast side of South Bight, especially large 

 series were collected, which were to serve for planting and as a reserve series 

 for comparison with the progeny of the transplanted material. 



On our return to the Florida coast, plantings of these two races were 

 made, as follows: May 28, 1912, there were planted 500 of No. 2, on the 

 sandy beach on the middle of the outside of the first of the Ragged Keys, 

 north of Sands Key; 500 of No. 1 were planted on the second of the Ragged 

 Keys, north of Sands Key ; also on the sandy beach on the outer shore. The 

 next planting was made on June 1, on Indian Key, where 500 of No. 2 were 

 placed about the old ruins of a house on the bay side of the key. On the 

 same day 500 of No. 1 were planted on the Tea Table Key. These were 

 also scattered about the ruins of the old house on the north side of the island. 

 On June 2 plantings were made on Bahia Honda, where 500 of No. 2 were 

 placed on the northwest side of the deep cut which runs parallel with the 

 outer beach, 500 more of No. 1 were planted on the south side of Duck Key. 

 On June 3 we planted 500 of No. 1 in the middle of New Found Harbor Key. 



Being unable to continue to the Tortugas with the party, since the time 

 allotted for my trip had expired, Doctor Mayer kindly made the following 

 plantings for me : June 8, 500 of No. 1 beneath the U. S. Coast Survey bea- 

 con, on the northwest end of Boca Grande Key. A planting of 138 of No. 1 

 was made back of a small unpainted house on the northeast side of the fort, 

 on Garden Key, Tortugas. On Loggerhead Key, Tortugas, three plantings 

 were made, as follows : 500 of No. 2 on the left-hand side of the path 

 (marked by a stake) between the light-house and the laboratory, 600 feet 

 north of the light-house ; 500 of No. 1 at the southern end of the island, also 

 marked by a stake, and another planting near the boat-house at the middle 

 of the western shore of the island, consisting of a mixture of 500 each of 

 Nos. 1 and 2. The southern planting is 1,000 feet from the middle, and the 

 northern 800 feet from the middle one. In addition to this, 73 specimens 

 of a small painted Cerion were planted on Bird Key and the place was 

 marked by a stake. 



All of the planted material, except the specimens left on Boca Grande, 

 were marked by making two fine parallel cuts with a file across the ribs on 

 the back side of the antepenultimate whorl, and all were adult shells. The 

 snails of all colonies planted upon the Tortugas appeared to be thriving well 

 in July 1912, but no young individuals were observed. 



During our cruise from Miami to Key West, a special effort was made to 

 examine as many of the keys as we could reach conveniently for Cerion 

 incanum Binn., and wherever found to gather as large a series as possible. 

 It was observed that most of the keys which had been flooded during the 

 hurricanes of 1906 and 1910 contained practically no live Cerions, though 

 dead ones were observed in a number of places, and this caused one to won- 

 der whether sea-water, as such alone, might serve as a decided barrier to 

 these forms. This also seemed to be indicated by the fact that the living 

 Cerions collected were always found beyond the reach of the ocean spray, 



