On sandy shores the greater part of the inhabitants live under the surface. Many give evidence of their presence by the open mouths of their burrows, and some distinctly point out these places by piles of sand or mud in coils at the opening. Some tubicolous worms have their tubes projecting above the surface. The tubes of /Diopatra/ are hung with bits of shells, seaweeds, and other foreign matter. Some mollusks announce themselves by spurting jets of water or sending bubbles of air from the sand. The majority of the underground species, however, give no sign of their presence on the surface, and must be found by digging. Many of them go deep into the sand, and in searching for worms the digger must be quick- and expert, or he will lose entirely or cut in two many of the most beautiful ones, which retreat quickly and to the extremity of their holes at the least alarm. One can be a rambler on the sandy beach for a long time without being aware of the many beautiful objects which inhabit the subsurface of the sand. The curious crab /Hippa/ will disappear so quickly into the sand that one is hardly sure he has really seen it. The vast number of worms will surprise any one who searches for them by their variety, their beautiful color, and their interesting shapes. Here again a glass is requisite to appreciate the delicacy and beauty of their locomotive organs, their branchiæ, and so on. The most common of the gasteropod mollusks on sandy shores are /Nassa obsoleta/, /Nassa trivittata/, and /Polynices (Lunatia) heros/. The last are detected by the little mounds of sand which they push before them as they plow their way just below the surface. On more southern beaches, /Fulgur/, /Strombus/, and /Pyrula/ are the common varieties. /Olivella/, /Oliva/, and /Donax/, also inhabitants of sandy beaches, will quickly disappear when uncovered by the waves, being rapid burrowers. Most of the many dead shells on the beach will be found to be pierced with a round hole, which is [pg011] drilled by the file-like tongue, or lingual ribbon, of /Polynices/, /Urosalpinx/, or /Nassa/, which thus reach the animal within and suck out its substance. Another similar species is /Polynices/ (/Neverita/) /duplicata/, which extends to the Gulf of Mexico, while /P. heros/ is not commonly found below Hatteras. Crustaceans are abundant on the sandy beach over its whole breadth. Some of the sand-crabs live above tide-mark. Among these is the fleet-footed /Ocypoda/, which is interesting to watch. Often they go in numbers to the water's edge and throw up mounds, behind which they crouch like cats, watching for whatever prey the tide may bring up. When unable to outrun a pursuer they rush into the surf and remain there until the danger is past. The wet sand is often thickly perforated with the burrows of the sandhoppers (/Orchestia/). These often rise about the feet as do grasshoppers in the fields.