1913.1 NATURAL SCIENCES OF PHILADELPHIA. 



VARIATION IN TWO SPECIES OF LUCIDELLA FROM JAMAICA. 

 BY AMOS P. BROWN. 



The genus Lucidella is best known from species found in the 

 island of Jamaica, from which locahty the first species were figured 

 by Ferrusac^ under the name of Helix aureola. Ferrusac then figures 

 the two common species of Jamaica, which appear to have a general 

 distribution throughout most parts of the island. These species 

 are very plentiful in the interior of the island, particularly in the 

 Mandeville region. They live in the more undisturbed parts along 

 the borders of woods, seeming to prefer situations where there is a 

 certain amount of sun, rather than in the dense woods. Along 

 the roads they are met with inhabiting the stone walls, which are 

 the common fences in this part of the island. When once established 

 in the walls they appear to flourish, even when the woods are cut 

 away from the vicinity of the roads, and where they have plenty 

 of cover and not too much dryness they develop into as large forms 

 as in the more undisturbed regions. Lucidella aureola (Fer.) is 

 probably more generally and widely distributed, but L. granulosa 

 C. B. Adams is more plentiful in the Mandeville country, though 

 both forms are found living together. Along grassy roadsides with 

 low limestone rock exposures and even where the red residual clay 

 from the limestone forms the banks of the road they are found 

 in numbers; in the case of the red clay banks, perhaps L. aureola 

 is somewhat more common, while L. granulosa is found more fre- 

 quently in numbers where the limestone exposures are seen. This 

 habit of living along the borders of woods and in the more open 

 rocky woods is common with both species in the more undisturbed 

 regions where the original forest still exists. 



These two species have adapted themselves to the conditions 

 brought about by advancing civilization and clearing of the land, 

 and are well established, even in the oldest settled districts, being 

 found in numbers in many places that have been quite stripped of 



1 D. de Ferrusac and G. P. Deshayes, Hist. Nat. des Mollusi^ues, Vol. 3, 1820- 

 1851, PI. 48, 1, three figures oilLucidella aureola (Fer.) and PI. 49A, 1, two figures 

 of L. granulosa C. B. Adams, all figured by Ferrusac under the name of Helix 

 aureola. 



