THE ANIMAL LIFE OF THE GROUP. 465 



brown in color, are usually banded with chocolate, and have the aperture 

 often streaked with the same color. Two other genera ^- belonging to this 

 family also occur about the shores of the islands. They are small shells seldom 

 seen by amateur collectors, and differ so much in appearance from the more 

 common forms that their relationship is not easily understood. The Fossaridce 

 is a small family closely allied with the family just considered, the chief dif- 

 ferences being in the soft parts. The family PJanaxidce is a small family, the 

 common species ^^ being nearly smooth, light yellowish varied with orange, 

 brown and chestnut, is little over a quarter of an inch in length and varies 

 greatly in form and color. The Eissoidce include another group of shells to 

 which a dozen or more forms from Hawaii have been referred. Of this num- 

 ber five or six small species may occasionally be taken among the very small 

 shells on the shore, but they are too tiny to be of interest to anyone except the 

 professional collector. 



Sea Snails. 



The sea snails^'* include such well-known shells as the small black species 

 commonly found clinging to the lava rocks along the shore near the upper 

 tide-mark. They are all fond of seaweed and are nocturnal in their habits, 

 the thick body whorl and small spire give them a characteristic form, but they 

 may be identified also, by the character of the operculum, which is iieculiar 

 in that it has a process jetting out from beneath that fits under the toothed or 

 wrinkled columellar lip, when the animal retires within its shell. 



Of the six species of Xerifa reported from Hawaii, the black form witii 

 a white ajierture and with fine spiral grooves on the shell is most abundant on 

 the sea-shore of Oahu. It is commonly known as pipipi.^^ The native Ha- 

 waiians are very fond of them and often spend hours gathering the little black 

 shells from the rocks at low tide. The fleshy part is easily picked from the 

 shell with a pin after they have been heated in warm water or in the imu — the 

 native underground oven. A similar species,^*^ which is without teeth on the 

 outer lip, and a larger variegated species •"*" showing fine growth lines and with 

 the shell flecked, spotted or banded with white, yellow, orange, red or black 

 on a varying ground color, are fairly common about the islaiuls. Both these 

 latter species, and doubtless others, were used by the natives in bracelets worn 

 as an emblem of mourning for the alii. A specimen in the author's collection 

 is shown on the accompanying plate. They were often polished or cut in 

 various shapes. 



A genus ^s belonging to this family, which has four or five Hawaiian 

 species, is not easily separated from their cousins just described. They are 

 somewhat thinner shells and are usually found under stones or clinging to the 

 rocks just below the low-water mark, most coimiionly in the brackish water 



°- Modulus tectum ar.d RisHIa spp. "-^ Plnnn.Hs liiipatu.i. ■■* ycritiihr. "^ Xerita picea. 



=« Nerita sp. °^ Kerita polita. '^ Xeritina. 



