20 PROCEEDINGS OF THE ACADEMY OF [1888. 



dependent culminating peaks. The aggregate length of the two 

 ranges is 50 miles. The sides of these ranges, their entire length, 

 are furrowed by deep valleys separating lofty ridges. These val- 

 leys and ridges are the home of Achatlnella : each valley and 

 ridge has its own distinct species which are connected with those of 

 the next valley and ridge, by a multitude of intermediate varieties, 

 presenting minute gradations of form and color. These two ranges 

 of mountains have already furnished 227 distinct described species 

 of Achatinella, the number of varieties has been estimated as high as 

 800 or 900. All these species and varieties, are found in an area of 

 less than 120 square miles ; and a considerable portion of the longer 

 range remains yet to be explored. These species have all the va- 

 rious shapes from globose to conic, ovate and elongate-conical, and 

 present almost eveiy possible shade and variety of coloring, from 

 pure white to jet black, and all the shades of green, rose, yellow, 

 brown and ash ; sometimes several of these colors are combined in 

 one species, either in regular or irregular bands, or tessellated, mar- 

 bled or zigzaged designs." 



"West Maui. On this part of Maui we have the converse of 

 Oahu. Its individual mass of mountains, clustering around one com- 

 mon centre peak, 2000 feet higher than any part of Oahu, furnishes 

 only 30 described species of Achatinella, each principal valley and 

 ridge has its own peculiar species or varieties ; but all the arboreal 

 species can be referred to seven leading types, these differ much from 

 the Oahu types, and do not present the same varieties of form or 

 color. The prevailing colors are white and dark brown with all the 

 intervening shades ot either, plain or variously arranged in bands 

 or zigzaged lines." 



" East Maui. The distribution of Achatinella on this part 

 of Maui is not fully known. All its mountain gorges and ridges 

 concentrate around the rim of the immense crater of Haleakala, a 

 circumscribing bound of nearly thirty miles in extent. The almost 

 impenetrable forest on the mountain slopes to the east and south 

 of the crater comprising a belt of twenty miles long and six miles 

 wide, remain unexplored, and its molluscan life is unknown. The 

 woodlands on the north-west slope of the mountain facing West 

 Maui furnish 29 described species of Achatinella ; but they are the 

 same or unmistakable counterparts of those found on West Maui. 

 The narrow depression of land between East and West Maui has 

 led many to infer that they were originally separate islands, this 



