52 Ml- Logan on the Ihibi/s of Testaceous Mollnsca. 



pulling them off. The animals seem to be provided with this 

 gum in great abundance, for a shining white streak marks 

 their course wherever they go, so that, by getting upon an 

 elevated place, the trees which they inhabit may easily be 

 distinguished. They seem to live in societies, it being rare to 

 fall in with a solitai7 straggler, and only inhabit a tree here 

 and there. 



On farther prosecuting these obserA\ations, 1 found that 

 those glued to a tree or to leaves, as above stated, like the 

 operculated Achatina, shewed little or no signs of life till 

 priclied or otherwise excited ; when they would retreat into 

 their shell, with a slow and almost imperceptible motion ; 

 some of them, in the same slow manner, gradually discharging 

 a quantity of water ; in others, the quantity was scarcely dis- 

 cernible. The latter, I supposed, must have nearly completed 

 their period of i-epose, as they could not live long after the 

 water was completely exhausted in their bronchiae. 



I had a great desire to mark the exact duration of time 

 these animals remain in this dormant state, but my stay in one 

 place was always too short to enable me to accomplish my 

 piu'pose. From the facts above stated, it would appear that 

 the moUusca contained in the shell just mentioned, at certain 

 natural periods, with which neither climate nor season have 

 any concern, go into a dormant and inactive state ; being pro- 

 vided, at the same time, with the power of shutting up the 

 mouths of their shells, either with a hard calcareous opercu- 

 lum, or by gluing them to other bodies with a strong gum. 

 Without this precaution they would be devoured, in their 

 dormant state, in a few hoius, by the ants which swarm 

 everywhere, being observed in myriads even on the tops of 

 the mangrove trees, where the tides rise and fall from tliir- 

 teen to fourteen feet, and where, in many places, they are 

 at least half a mile from di-y land. The first time I obser- 

 ved these mollusca on the tops of the mangrove trees, made 

 me natiu:*ally suppose that they were phytophagous, and that 

 they frequented the leaves for the purpose of feeding ; but, af- 

 ter examining the leaves with great care, no trace of gnaw- 

 ing or eating could be seen, even where they were in greatest 



