THE NAUTILUS. 7 



of the fungus and the white fly that badly infested groves and hedges 

 may be recognized at some distance by the heavily coated dark foli- 

 age. The fungus develops on the fruit as well as on the leaves and 

 stem, and washing becomes necessary, resulting not only in an added 

 expense, but also in increased danger of decay in shipping. In this 

 connection the habits of the tree snail, Bulimulus dormant, 'are of 

 the greatest interest. This snail has been found in the orange 

 groves in Manatee county feeding upon the sooty mould. Just how 

 long the snail has been present on orange trees in this county it is 

 impossible to say. It was observed as long as two years ago by Mr. 

 F. D. Waite, at Palmetto. It seems to have been present in small 

 numbers in other groves at this time, but attracted no further atten- 

 tion until the present summer. The snail is now widely distributed 

 in Manatee county, occuring in many groves on botii sides of the 

 Manatee river. The work of the snails is very characteristic. 

 When well started they occur in great numbers on the tree, spread- 

 ing over it from base to top. Its favorite food seems to be the sooty 

 mould. The fungus is cleaned from the leaves, stems, and fruit. 

 The leaves thus cleaned have a glossy, shiny appearance as though 

 free from white fly. The fruit thus cleaned has a better color and 

 probably ripens earlier. In addition to the fungus, the snail takes 

 algte and some lichens from the stem and trunk, giving the trunk a 

 much cleaner and fresher look. The trees that are cleaned stand 

 out conspicuously from the surrounding trees by their bright foliage 

 and clean trunks. The snails increase rapidly under favorable con- 

 ditions. The eggs are probably deposited in protected places about 

 the trunks of the trees, possibly also about the base of the tree under 

 leaves and other rubbish. That the snails are capable of doing ef- 

 fective work, when present in sufficient numbers, has been shown in 

 numerous groves in Manatee county during the present summer. 

 Such trees in these groves as are well stocked with the snails have 

 been thoroughly cleaned, the fruit not requiring washing. 



The snails are of medium size, measuring when full grown, three- 

 fourths to one inch in length. The shells are smooth, white, or 

 corneous-white, and with about four bands of brown spots. Old 



1 This species is now placed in the genus Drijnmus. A closely allied species, 

 D. dominicus Rve. (B. marielinus Poey), is also common throughout southern 

 Florida, and frequently confounded with dormant. It probably has similar 

 feeding habits. — Editors. 



