1888.] NATURAL SCIENCES OF PHILADELPHIA. 2ii 



are on rugged mountains, densely covered by vegetation and their 

 sides furrowed by deep and almost inaccessible ravines and large 

 districts on Oahu and East Maui wliicli have never been visited by 

 white men, remain yet to be explored. It will require years of re- 

 search and study, before the number and exact distribution of the 

 remaining sj^ecies can be ascertained. It is also generally supposed 

 that these shells are becoming extinct by the ravages of cattle through 

 our forests. This is true in respect to a limited number of species 

 on the island of Oahu whose habitats were the forests on the lowest 

 range of hills. Some of these hills have been denuded of woods, not 

 only by cattle, but the woodman's axe, and certain species are be- 

 coming rare. The favorite resorts of many species are the Ki (Dra- 

 cena terminalis) and the Olona (Boehmeria stipularis) both excellent 

 fodder plants. But in localities where these plants have been entirely 

 destroyed by cattle, the shells have generally selected homes on other 

 adjoining plants. The ravages particularly of wild cattle in our 

 mountain forests are certainly to be deprecated, nevertheless by 

 clearing the under brush they render the forests more accessible for 

 the collection of known species ; and by opening the paths to higher 

 and more dense forests they facilitate the discovery of new species. 

 The agencies now threatening the wholesale destruction of these little 

 gems of the forest are the rats and mice, which have become very 

 abundant in mountain forests, particularly where there are no cattle. 

 Their ravages are not confined to the shells whose habitats are on the 

 ground, but extend to those found on trees. It is not uncommon to 

 find around the charnal cells of these noxious little animals hundreds 

 of empty, mutilated shells. Not^Vithstanding these threatening agen- 

 cies, the Achatinellffi are still quite abundant on Oahu and Molokai, 

 where cattle have the widest range, though not so abundant as for- 

 merly on West Maui where the cattle ranges are somewhat limited 

 and the mice enjoy greater immunity. In a recent excursion with 

 a friend through a portion of the mountain forests between Ewa and 

 Waialuaon Oahu more than 3000 shells were collected in a few days 

 embracing over fifty species of Achaiinella, some of them new to 

 science. In a similar trip around Molokai nearly 5000 were collec- 

 ted, embracing thirty species, some new."^ 



To Wesley Newcomb, M. D. more than to any author on Acliati- 

 nella, we are indebted for a correct knowledge of the described spe- 

 cies of this beautiful genus of shells. During a residence of nine 



1 Mr. D. D. Baldwin in Hawaian Almanac and Annual. 



