206 Papers from the Department of Marine Biology. 



on the sea side. There are two lesser dead trees, one on each side of 

 the taller. The specimens were placed in a patch of grass near the 

 base of the outer dead tree, apparently a very favorable habitat. The 

 distance of this key from the first Ragged Key north of Sands Key is 

 only a few hundred yards; hence the environmental conditions are 

 probably very nearly the same in the two places. 



April 22, 1914- Visited Tea Table Key, and found no living cerions, 

 and only a few dead. Apparently this colony is doomed to extinction. 

 The island is infested with crabs, being riddled with their burrows, 

 and the small hermit crabs have probably carried off most of the shells. 



On Indian Key, 20 of the dead specimens were still on the wall where 

 we placed them last year, and 2 more were at the base where the 

 majority were strewn. A thorough search revealed only 13 living 

 specimens, so this colony also is on the verge of extinction. No young 

 individuals were found in this second planting. We next visited the 

 place where the original planting was made the place which was so 

 completely overrun with vegetation last year that it was deemed wise 

 to shift the colony a little further inland. The vegetation is even more 

 dense than last year and it was impossible to determine if any had 

 survived here. 



April 23, 1914- In the colony on Duck Key, 107 of the marked 

 shells were recovered, all but one alive. Many of these were copulating. 

 We found only one young specimen, but the vegetation here is so dense 

 that the small young could easily escape notice. The young indi- 

 vidual obtained possessed only one postnuclear whorl. All the shells 

 were put near the stake where we planted them last year, and it seems 

 quite possible that this colony may survive. 



The colony at Bahia Honda is doing well. We gathered 46 marked 

 specimens all that we could find and took them westward to the 

 summit of a little promontory, dropping them between the stumps of 

 two palms and marking the place with a stake. Across the ditch from 

 this stake stands a large palm. We did not wish them to mingle with 

 their grown or growing offspring, which are very abundant on this 

 plantation. We gathered 105 of the young and placed all but 13 at the 

 base of the old stake. The 13 are full-grown, or nearly so, and these 

 we took with us in order to compare them with the check series. (Plate 

 1, bottom row.) Even in the field the Florida generation appeared so 

 remarkably different from their Bahama-born parents that we could 

 distinguish them the moment we saw them. 



On New Found Harbor Key the ground where the planting was made 

 was swamped with a dense growth of some malvaceous plant which 

 was overgrown with a leguminous climber. Only 1 1 planted specimens 

 were found, and no young. The place was so fearfully infested with 

 mosquitoes that a long stay and exhaustive search was impossible, but 

 from observed facts I would say that this colony was not prospering. 



