NO. I ACHATINELLA APEXFULVA DIXON — WELCH I97 



the Bishop Museum's portion of the Gulick collection is measured, 

 with the exception of one Gulick lot of A. leiicosona in the Academy 

 of Natural Sciences of Philadelphia. This is approximately only 22 

 percent of the entire Gulick collection, which was broken up into 20 

 separate collections by Gulick. Many specimens were also traded 

 with people all over the world by Gulick, so that 22 percent may be 

 too high an estimate. 



The Gulick material used, therefore, cannot be statistically signifi- 

 cant, but does give an approximation of size variation of at least 

 those series which are measured. In the region of ridge complexes i 

 and 2 (table 2) 17+ shells are dominant in the Gulick lots, whereas 

 in the region of ridge complexes 14, 15, and 19 the mean length 

 ranges from 16+ to 17 + . The 19+ forms from the region of ridge 

 complex 15 are probably from zone II. 



Zone II shows marked size variation in certain regions. Groups of 

 ridge complexes have similar shell lengths and the change in some 

 regions from large to small shells is abrupt. Half the ridge com- 

 plexes (i, 4, 5, 7,* 8, 9, 15, 18, 19, and 20) contain mostly i8-t- shells, 

 22 percent (ridge complexes 10, 14, 16, and 17) have mostly larger 

 19+ shells, and 27 percent (ridge complexes 3, 6, 11, 12, and 13) con- 

 tain small iy-\- shells but may also have i8-f- shells. Small 16+ shells 

 occur only in ridge complex 1 1 . 



Twenty-two percent of the ridge complexes (i, 10, 11, and 12) in 

 zone III have small 18+ or 17-f shells. The remaining 78 percent of 

 the ridge complexes, including number 2 (fig. 8, p. 195) have 19+ 

 or 20 -f shells, and in ridge complex 8, 21+ shells also occur. Only 

 the uppermost localities in ridge complex 2 contain 19-I- shells, the 

 lower localities having small i84- or 174- shells. If size alone were 

 considered, these lower localities would be placed in zone II. In ridge 

 complex 3 (fig. 8, p. 195) what appears to be the highest area 

 contains 18+ shells. Actually this area (area 12, fig. 8) is on the 

 lower portion of a small spur ridge in ridge complex 3 and is at a 

 lower elevation than the other localities. Ridge complex 7 also has 18-I- 

 shells in zone III (area 31, table 2). This may be due to the 

 small number of shells measured; possibly if a larger series were 

 obtained, the mean length would be greater. 



* Area 27A ?, the lowest area in ridge complex 7, has a mean length of 

 18.77 mrn. and is therefore represented in figure 8 by the symbol for the 

 19 -f- class shells. However, it really is very close to the 18.5 class and could 

 be considered an 18 -}- area. 



