EXPERIMENTS IN THE BREEDING OF CERIONS. 



35 



Table No. 17. — Measurements of the first generation of Florida-grown Cerion casahlancoe 

 from the first Ragged Key north of Sands Key. 



able to find only 2 of the marked shells and 2 which belong to the second 

 generation. These are numbers 24 and 25 of plate 35. The original 

 planting about the house escaped the burning, but we fear that the new 

 buildings which are to be erected, as well as the human activities which 

 are to be displayed upon this key, will probably table No 18 



exterminate this planting. The measurements 

 of two specimens of the second Florida-grown 

 generation are given in table 18. 



The Colony on Sands Key. 



In April 1914 we planted 50 tips, varying in 

 size from nepionic shells to half-grown indi- 

 viduals. These were placed in the middle of 

 the first sand stretch south of the north end on the seaward side. 

 The place is marked by a skinned, bleached, white tree, which forms a 

 conspicuous landmark on the sea-side. There were two lesser dead 

 trees on each side of the taller stump. The specimens were placed in a 

 patch of grass near the base of the outer dead tree, which appeared to be 

 a very favorable habitat. 



In June 1915 we found only a single half-grown specimen, and since 



then not one has been discovered. Previous experience, however, 



would lead us to believe that it is possible that members of this little 



colony may still survive and in course of time may populate the 



region. 



The Colony on Indian Kjey. 



On June 1, 1912, we placed 500 specimens of Cerion casablancce about 

 the ruins of an old house on the bay side of the key. When we visited 

 this planting on April 26, 1913, the Cerions were doing well, some of 

 them having moved fully 60 feet from the place where they had been 

 dropped. Most of those seen were on dead sticks, usually clustered in 

 groups, though many were on the rank growth of Sesuvium portulacas- 

 trum which threatens to overrun the place. We found 20 of the planted 



