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where it was reported to present such unusual structural characteristics 
as to make it possible that it should he referred to a new genus, but 
the point could not be settled as both my specimens are males. 
[Plate III., Eig. 6.] 
One day during a meal at Constant Spring I saw a curious spider 
(? Gasteracantha sp.) spinning a web on a rose in a flower-vase; its 
abdomen was protected with a hard spine-bearing carapace. 
NOTES ON THE LAND MOLLUSCA OF JAMAICA. 
By Mrs. G. B. Longstaff, F.L.S. 
Jamaica is well known to be one of the richest regions in the 
world for land shells. Unfortunately we were there in the dry 
season, so it was more or less difficult to procure living specimens, 
nevertheless we managed to get a fairly representative series. Dead 
shells were found in great numbers and often in a remarkably good 
state of preservation. The wide extent of limestone is probably 
one reason for the richness of the molluscan fauna. Shells were 
observed to be most numerous on the limestones of Tertiary age, 
especially on the “ White Limestone ” of Oligocene age. 1 There were 
nothing like as many specimens on the limestone of Pleistocene 
age ; this was very noticeable in the neighbourhood of Port Antonio, 
where both formations occur. 
Shells were met with in great numbers in recesses or cavities 
of the limestone, also under loose stones in the so-called sinks. 
They were not only found thus in the wild uncultivated parts, but 
also in banana and yam plantations, where they were living both 
under stones and under leaves, and also attached to the stems of 
trees. Their frequency in cultivated ground stands in marked 
contrast to their absence from such habitats in other countries. In 
New Zealand, for instance, it was rare to find any but introduced 
species in gardens, quarries, &c., endemic forms being confined to the 
bush and other uncultivated land. This was also more or less the 
case in Ceylon. 
None of the land shells of Jamaica attain a very great size, the 
largest being decidedly smaller than the well-known Bulimus 
oblongus, Mull., of Barbados and Tobago. Many, however, are 
characterized by great beauty of form and colour, and some are 
remarkable for the development of numerous teeth which in certain 
instances almost close the aperture, so that it is a matter of wonder 
1 “ Geol. and Phys. Geogr. of Jamaica,” by R. T. Hill, 1899. 
