THE ANIMAL LIFE OF THE GROUP. 461 



are represented in Hawaii ])y two species, there bein<i' hut fifteen species 

 described. The partridge tun -' is the more common, though a specimen is a 

 real prize. It is fairly t.ypieal of the family. The tun is a large shell wnth a 

 stout spire and sw^ollen body-whorl that is banded l)y strong spiral ribs. The 

 shell is marked with crescents and irregular lines of white on a rich browm 

 ground color, suggesting the breast of a partridge. They are said to attain a 

 length of fifteen inches, but the specimens found on the beach are seldom more 

 than a third that size. The black-mouthed tun ^s is much rarer. It is dirty 

 white in color and has the outer lip dark brown. 



Cameo Shells. 



The helmet or cameo shells -^ are active predatory moUusks that live 

 along sandy shores in the warm seas. There are perhaps three dozen species 

 and sub-species, of which five or six are known to occur in the w^aters about 

 Hawaii. They all agree in being thick, heavy shells witli short spires. The 

 aperture is long and ends in a recurved channel. The typical horned helmet ^^ 

 occurs in the islands. Although it is a rare shell here, it is of more than ordi- 

 nary interest since it is one of the shells used elsewhere in the manufacture 

 of cameos, cutting a white figure on an orange-brown ground. It is the giant of 

 the family, reaching a foot in length. The shell is yellowish-white tinged with 

 yellowish-brown, and is studded over the back with three rows of tubercles. 

 Blotches of dark brown occur on both the curiously expanded lips and on 

 the knobs. 



The more common form on Oahu is Cassis vihex, which has four short 

 spines at the base of the lip and is seldom more than three inches in length. 

 It is a fieshj^-ash color, obscurely banded and varied wdth light and dark chest- 

 nut. The lip on its outer margin is marked with chocolate spots. A variety ^^ 

 also occurs that is smaller, thicker and has small elongated tubercles on the 

 shoulder. 



jMoon Shells. 



In the family of moon shells, or naticas,^- the shell is more or less globular 

 or eai^-shaped and the aperture differs from that of the preceding families in 



^' Dolium perdix. "'' Dolium rtielanostonia. -^ Cassidcc ^"Cassis cnrnuta. 



3^ Cassis vihex erinacea. ^^ Naticidoe. 



(Drsrription of Plate Continued from Opposite Page.) 



pilearis). 4. Quilted Triton (Triton luhcrunus). 5. Spindle Shell (Fiisus novor-hoUandice). 

 6. Chocolate-lined Cone {Comis quercinm). 7. Lettered Cone (Conns pnlivarius). 8. He- 

 brew Cone (Conns licbrceus). 9. Conus lividus. 10. Conus miliaris. 11. Auger shell sp. 

 (Tereira sp.). 12. Terebra gouldi. 13. Terebra ocnlala. U. Terebra aeiculina. 15. 

 Hermit Shell (Camis vibcx var.) . 16. Hawaiian Top Shell (rrochu^ .mndwicen.'iu'i). 17. 

 Hump-l)aeked Cowry [Leho] (Cyprwa manritiana). 18. Ci/pro'a reticulata. 19. Turban 

 Shell (Turbo chrysostomus) . 20. Turbo intrrcostalis ; showing the operculum in place. 21. 

 CyprcFa svlcidentata. 22. Worm Shell [Tohokupelel (rrrmrhis sp.). 23. I'lrwctns sp. 24. 

 Kaunoa (Vermetus sp.). 25. Partridge Tun [Puonionio] (Doliiim perdix). 2(5. Umbrella 

 Shell [Opihi kapuailio] (JJelcioniscus exaratu.^). 27. Conoid Harp SIioll (TIarpn ronoidalis). 



