IQO SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. IO3 



are shown, which distinguish the area containing them from another 

 area of similar shells. 



A. Horizontal Variation 



I. COLOR PATTERN OR COLOR OF THE EMBRYONIC WHORLS 



On the color of the embryonic whorls the subspecies oi A. apexfulva 

 are segregated into four regions. Regions I and III have shells with 

 bicolored embryonic whorls, and regions II and IV have unicolored 

 embryonic whorls (fig. 7, p. 194). These four regions are further 

 subdivided into intermediate regions la (area 19), Ila (areas 48, 

 48A, and the localities of area 47 occurring on the Manana-Waiawa 

 Ridge), Ilia (areas 41, 42, 43, 63, and 64), Illb (areas 61 ? and 62?), 

 which contain intermediate or border forms between those of the 

 main regions. The embryonic whorls of these border forms have a 

 color pattern similar to that found on the shells at a similar elevation 

 on the next parallel ridge to the southeast. This is also true of areas 

 40, 49, and 50. 



In region Ilia the embryonic whorls are white, cream buff, or tan, 

 faintly lined or banded with a lighter or darker color. They are 

 intermediate between the white unicolored embryonic whorls of the 

 group of A. a. turgida (region II) and the yellow banded bicolored 

 embryonic whorls of the group of A. a. polyinorpJm (region III). 



Region Illb and areas 40, 49, and 50 definitely have the same 

 colored embryonic whorls as found on the adjacent parallel ridge to 

 the southeast. Region la contains shells with embryonic whorls which 

 are still bicolored similar to the group of A. a. simulans (region I) 

 to the southeast but are approaching the unicolored condition of the 

 shells in region II. Region Ila has shells with sHghtly bicolored 

 embryonic whorls intermediate between region II and III, but closest 

 to the unicolored embryonic whorls of region II. 



2. COLOR PATTERN OR COLOR OF THE POSTEMBRYONIC WHORLS 



Many difficulties are encountered in distinguishing subspecies using 

 color pattern for a criterion, because the same color pattern occurs 

 again and again in colonies of shells in widely separated areas. For 

 example, the dark typical apexfulva pattern from area 97 or one very 

 similar to it, may be found in area 35 {A. a. turgida) (fig. 7, p. 194), 

 area 94 {A. a. bcata var. i), area iii {A. a. paumalucnsis) , area 114 

 {A. a. oioensis). Pink patterns such as A. a. lilacea var. i in area ^^ 

 and A. a. lilacea possibly in area 83b ? ? may also be found in area 81 ? ? 



