CHAPTER LXVIII: THE AGATE SHELLS 



Family AcHATiNiDiE 



Shell thick, ovate, with elongated spire, and ventricose 

 body whorl; aperture oval, large, sometimes on the left side; 

 columella twisted, arched; lips united by a shiny callus. 



Some agate shells are larger even than the great Brazilian 

 snails, Bulimus. They, too, lay white eggs, over an inch long. 

 In truth the Achatinae in Africa are parallel in characters, as in 

 latitude, with the Bulimi in South America. But the agates are 

 tree snails, and so dare to be gaily marked, while Bulimus, the 

 ground snail, must be dull. 



Genus ACHATINA, Lam. 



Shell oblong-oval; spire conical; aperture oval; whorls 

 rounded, six to nine, sometimes sinistral; lips united by a shiny 

 callus. About seventy-five species, living in trees. Tropical Africa. 



A. variegata, Lam., dull tan-coloured with broad streaks 

 of dark brown running full length of the shell, is one of the largest 

 species. Length, 6 to 8 inches. West Africa. 



The Zebra Agate Shell (A. ^ebra, Lam.) is streaked with 

 zigzag longitudinal lines of chestnut on a white ground. The 

 shell is ovate. Length, 4 to 5 inches. Madagascar. 



A. sinistrorsa, Chemn., one of the largest agates, coils to 

 the left. It has a lurid brownish body whorl, with bright, chesnut- 

 streaked spire. Length, 4 to 5 inches. Isle Principe, Africa. 



A. reticulata, Pfr., has a slender, creamy white spire of 

 gracefully rounded coils, finely streaked and dotted with chestnut. 

 The shiny surface is raised in fine rounded ridges crossed by 

 close spiral grooves. Length, 6 to 8 inches. Africa. 



A. purpura, Chemn., horny outside, has a rosy lining. 

 Length, 3 to 5 inches. West Africa. 



The Panther Agate Shell {A. panthera, Pfr.), striped and 

 tawny like its namesake, lives in hollows in the rocks and in trees, 



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