. The sea-beach at ebb-tide : a guide to the study of the seaweeds and the lower animal life found between tidemarks . ly indicate that gasteropods belonging to this suborderare a step higher in the scale of life than those which belong tothe Diatocardia. FAMILY Janthina The genus JantJiina has an exceedingly thin and semi-trans-pareiit shell, deep violet in color on the base and lighter blue onthe spire. An interesting feature of this genus is the mode of de-positing the ova. The female exudes from a gland in the foot a GASTEROPODS 3G5 glutinous secretion which hardens in wat
. The sea-beach at ebb-tide : a guide to the study of the seaweeds and the lower animal life found between tidemarks . ly indicate that gasteropods belonging to this suborderare a step higher in the scale of life than those which belong tothe Diatocardia. FAMILY Janthina The genus JantJiina has an exceedingly thin and semi-trans-pareiit shell, deep violet in color on the base and lighter blue onthe spire. An interesting feature of this genus is the mode of de-positing the ova. The female exudes from a gland in the foot a GASTEROPODS 3G5 glutinous secretion which hardens in water, and, being filled withair-bubbles, constitutes a float. On the under side of this aredeposited the eggs in rows of little capsules. While attached tothis float it is impossible for :i -hnitliina to sink, and hence it isthat so many of these creatures are sacrificed in onshore gales ofwind. J. fittf/ilis. The shell of this species is so brittle and fragile that itis very clearly not adapted to a life near shore. It is in reality a pelagicspecies which is occasionally blown ashore during easterly gales along FL. .liiiithiiiii /rii-jilix: FL, float; O, ova; Pi; proboscis; Kr, branchiw ; F. foot. the Atlantic coast of the United States. Vast numbers of these prettycreatures are sometimes encountered far out at sea, floating quietly onthe surface. When storms drive them upon the beach, they becomeutterly helpless; since their foot is not adapted for crawling upon thesand, they soon perish, and their brittle shells are demolished by thesurf. In Florida the beaches are sometimes fairly lined with Ja nth innshells, which make a band of purple along the high-tide mark as far asthe eye can reach; then it may be years before they again appear.(Plate LXVIII.) FAMILY SCALIDJE GENUS Scala The shells of Smfn have such a peculiar scheme of decorationthat once seen they can never be mistaken. They are generallypure white, with well-rounded whorls, all of which are crossed ateven distances b
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