THE ANIMAL LIFE OF THE GROUP. 451 



Dog Whelks. 



The dog whelk *^ family has four species occurriug iu the islands, all 

 belonging to the one genus *^ of fish-basket shells. The name is given them 

 from the resemblance of certain species to the tapering narrow-mouthed 

 wicker baskets used in Europe by the fishermen in the fish and lobster business. 

 The small notch at the base of the aperture is an important characteristic. 

 They are predatory '" iu habit and are usually found near the shore. The 

 largest species "'^ is whitish, more or less blotched with yellowish-brown, and 

 has the spire tipped with pink. The various species of the genus seem to 

 intergrade to a remarkable degree. To the common small, light-yellowish or 

 orange-brown specimens with a pale central band is given the name Na^sa liirta. 

 The one with narrow red revolving lines and irregular broad bands, a variable 

 species, is called Nassa gaudiosa, while Nassa splendidula. smaller than the 

 foregoing, is white, .shining and distinctly granose, caused by the crossing of 

 the longitudinal ribs by deeply incised lines. 



JliTRE Shells. 



The mitre shells collected in the islands are usually included in the great 

 genus which is typical of the family,-'- according to the best authorities, al- 

 though this large genus is variously divided by other specialists. Three or 

 four additional genera, including the small "gutter-tile" sliells,^^ which ap- 

 proach the cone shells in general form ; the little turret shells,^"* of which there 

 are four or five species, and a small, slender representative of the genus Thala 

 are regarded as forming good genera, but they all have characteristics that 

 are common to the true mitre shells, and all may be known by their sharp 

 spire and the conspicuous and strongly marked folds on the columella. How- 

 ever, their size and the character of the body of the shell varies greatly, espe- 

 cially in sculpture and marking. There are more than two hundred species of 

 mitre shells in the tropics, and some of them are of large size and great beauty. 

 Of that number more than three dozen species, most of them less than an inch 

 and a half in length, have been reported as occurring in the waters about 

 these islands. Of a possible twenty-six species, seventeen of the genus Miira 

 have been collected from Honolulu harbor by the author. 



The living shells are gregarious ^^ and avoid the daylight by hiding in the 

 masses of coral on the reefs or liy Inirrowing in the sand. At night, however, 

 like many of their marine associates, they creep out to feed. Their heavy, hard 

 shells will long resist the action of the waves, so that they are to be found 

 among the small pebbles on the shore. On almost everj' ramble by the sea 

 the careful collector may gather one or more species of these attractive shells. 



By reference to the accompanying plates they can readily be identified as 

 ilitra. a name given out of a fancied resemblance to a priest's mitre; but to 



*s Nassidcc. ** Xassa. s" That is, feeding on other animals. ^^ \tissa papilloga. ^- Mitridfp. 



^3 ImbricaTia. ^* Turricula. ^^ Inclined to gather in companies. 



