[Illustration: PLATE I. Egg-capsules of Purpura lapillus. Egg-case of Polynices heros. Egg-capsules of Buccinum undatum. Egg-case of the skate. Fulgur canaliculata (whelk) and egg-cases.] /Hippa talpoida/ is a remarkable crab, somewhat resembling an egg. It is not likely to be seen unless searched for by digging at the water's edge. It burrows so rapidly that one must be quick to catch it after it is exposed by the shovel. In some places the tests of "sand-dollars" are common. The living animal may be found buried just below the surface at extreme low-water mark. The sea-wrack drifted in lines along the shore will repay careful examination, for here will be found many things belonging to other shores and deep water. It is often alive with sandhoppers, which hop away while one searches for less common things. Often the most delicate seaweeds, numerous small shells, worms, polyzoans, etc., will be found there. The surface of the sand-beach is strewn with remains of many species, usually beach-worn, but interesting nevertheless as examples of species one would like to find in better condition, but good specimens of which elude ordinary search or are unobtainable except by dredging. Egg-cases form another class of objects which are often gathered with no idea of their identity. Of these the most common are the long strings of saucer-like capsules which contain the eggs of the mollusk /Fulgur/, those having square edges being [pg012] the egg-cases of /F. carica/, and those having sharp edges those of /F. canaliculata/. Collar-like sandy rings contain the eggs of /Polynices/ (/Lunatia/), which are cemented together in this shape. The boys of Cape Cod call them "tommy-cod houses." Cylindrical piles of little capsules, sometimes called "ears of corn," hold the eggs of /Chrysodomus/. The irregular masses of small hemispherical capsules are those of the common whelk (/Buccinum/). The so-called "Devil's pocket-books" are the egg-cases of the skate. MUDDY SHORES