1911.] NATURAL SCIENCES OF PHILADELPHIA. 127 



trend. The crest of the main ridge is reached by taking a branch of 

 the upper Santa Cruz Road, which leaves the post road about 3 miles 

 to the west of Mandeville Court House and runs among the hills to 

 Lincoln. At about 6 miles west of Mandeville and somewhat short 

 of the hamlet of Lincoln the main ridge is crossed in a gap occupied 

 by this parochial road, and from this point the ridge was followed some 

 half-mile to the north-northwest. Near the road the larger trees have 

 been cut, but following along the rocky hill-crest one soon passes into 

 untouched virgin forest. From the top of this crest the Santa Cruz 

 Mountains may be seen some 10 miles away across the Valley of Black 

 River. The ridge is formed of the purer limestone, honeycombed by 

 holes and small cockpits, and standing up in sharp spires. The hill 

 is covered with a dense growth of jungle. The elevation of the highest 

 point reached was about 2,800 feet above sea level. Zaphysema 

 macmurryi, Pleurodonte jamaicensis, P. acuta goniasmos and species 

 of Sagda were very plentiful. Their dead shells were seen, in rifts in 

 the cliffs and in the cockpits, by the peck. The smaller holes in the 

 limestone were frequently several feet deep, the cockpits were often 

 ten feet and more deep. Careful search was made for living Zaphysema 

 macmurryi and P. jamaicensis, but while dead shells of both species 

 could have been gathered by the bushel (and many of these were in 

 perfectly fresh condition), no living specimens were encountered. 

 They probably live deep in the holes of the limestone and in the 

 cockpits, and would hardly be seen alive on the surface unless during 

 the rains, which at the time I collected here, May 3, had hardly begun. 

 The conditions of moisture and the character of the vegetation resem- 

 bled those of the Garrett's woods locality, but in this case the ridge is 

 continuously wooded for some miles with scarcely a break and the 

 forest extends down the slopes for a considerable distance, so that 

 there must be several thousand acres of woodland along this ridge 

 that is more or less continuous. The breaks that occur in the con- 

 tinuity of the forest could probably be crossed by migrating snails 

 during the rainy season, though, at the time of my visit, the dry slope 

 at the end of the hill towards the road would have offered an impassable 

 barrier. To the north, however, it must be nearly continuous forest 

 to Balaclava and the uncultivated Cockpit Country. To the northeast 

 lies the Somerset colony, in a similar forested area, but the intervening 

 valleys are many of them cleared and cultivated. The part examined 

 could be strictly called one colony, but, doubtless, on following out 

 the ridge to the north, many more or less isolated colonies would be 

 encountered. 



