EXPERIMENTS IN THE BREEDING OF CERIONS. 



37 



Uniola paniculata, and cacti. The planting in the interior was in even 

 worse condition, for, in addition to the cacti and other rank vegetation, 

 a complete invasion of huge agaves covered the territory and made it 

 literally impossible to move about except where one actually cut a path 

 through the bayonet-like agave leaves. We were therefore unable to 

 secure any material of the second generation from this colony. 



THE COLONY ON BAHIA HONDA KEY. 



On June 2, 1912, we placed 500 specimens of Cerion casablancce on the 

 northeast side of the deep cut which runs parallel with the outer beach. 

 The ground supported a scattered growth of palmetto and grass. 



On April 22, 1913, the place was completely overrun with sand spurs, 

 Cenchrus echinatus, in full fruit, which made a search for mollusks a 

 trying task. 



On April 23, 1914, we found 10 adult specimens and 3 nearly adult 

 of the first generation of Florida-grown individuals. The measure- 

 ments are shown in table 20 and the figures of the specimens are shown 

 on plate 5 of the 1915 report. 



On April 26, 1915, the colony was visited again and 58 full-grown 

 individuals of the first Florida-grown generation and 23 ranging from 

 quarter-grown to almost full-grown were found. Most of these speci- 



TABLE No. 20. Measurements of the first generation of Florida-grown Cerion casablancce 



from Bahia Honda Key. 



* Length estimated. 



** Shell not quite adult. 



mens were in the ditch. The material on top of the flat seemed to have 

 been completely wiped out by a destructive fire that had swept part of 

 the key. We marked and measured 56 and planted 55 of them. For 

 measurements see table 21 and for figures see plates 36 and 37. 



On May 20, 1916, we again visited Bahia Honda Key and found 22 

 full-grown specimens of the first Florida-grown generation; some of 

 these were fully 150 feet from the stake where they were originally 

 planted. Not a single specimen of the originally transplanted material 

 was evident and it seems as if all of these had perished in the fire of 

 1915 to which we have referred. In 1916 the snails were largely con- 

 fined to the inner edge of the ditch. The colony of Florida-grown 



