hermit crab, a crustacean distinguished from true crabs by its long, soft, spirally coiled abdomen terminating in an asymmetrically hooked tail. Most hermit crabs protect this vulnerable portion of their bodies by occupying the empty shells of periwinkles, whelks, and other gastropod mollusks. A few find other homes; for example, a species that inhabits the Indian Ocean lives in sections of old bamboo cane. When the hermit crab grows out of one shell it seeks a larger one, fighting for it if challenged. Sea anemones often attach themselves to these shells, obtaining free transportation and scraps of food in return for protecting their hosts. Hermit crabs are common beach scavengers in most parts of the world. Most species are marine, but some tropical forms, such as the robber crab, Birgus latro, are largely terrestrial. This species, the largest hermit crab, generally reaches over 1 ft (30 cm) in length. It becomes increasingly terrestrial and develops heavy armor as it matures into an adult, at which stage it is able to completely discard its adopted shell. With its great pincers the robber crab has been known to crack coconuts, which it obtains by climbing palm trees. Hermit crabs are classified in the phylum Arthropoda, subphylum Crustacea, order Decapoda.

hermit [Gr.,=desert], one who lives in solitude, especially from ascetic motives. Hermits are known in many cultures. Permanent solitude was common in ancient Christian asceticism; St. Anthony of Egypt and St. Simeon Stylites were noted hermits. Many extreme Franciscans (Spirituals) of the 13th and the 14th cent. were hermits, among them Pope St. Celestine. In the East the hermit, or eremetical, life was widely held to be the more perfect form of monasticism and was open only to those who had first passed years in a monastic community. Monasticism in the West developed along the less rigorous communal lines; the Carthusians are well-known exceptions. The hermit or anchorite of the ancient church lived in the desert, commonly walled up in a cell with only a window. In medieval Europe the cell usually connected with a church. The Ancren Riwle was written for English anchoresses. Juliana of Norwich was a famous English anchoress.

Peter the Hermit, c.1050-1115, French religious leader. In 1095 he was a very successful preacher of the First Crusade (see Crusades), and he led one of its bands. In 1096 he reached Constantinople with his undisciplined followers; when they arrived in Asia Minor, Peter went back to get help from the Byzantine emperor Alexius I. In 1098 at Antioch he tried to run away; however, he later undertook a mission to the Muslim ruler of Mosul. He went home after the taking of Jerusalem and founded the monastery of Neufmoutier at Liège, where he settled. His place in the Crusade was greatly exaggerated, for he seems to have been only one of many preachers and leaders, although a very early one.

Hermit Kingdom: see Korea.

Any crab (families Paguridae and Coenobitidae) that uses empty shells or other hollow objects as a shelter for partial containment and protection of the body. They are found worldwide in sandy- or muddy-bottomed waters and occasionally on land and in trees. They have two pairs of antennae and four pairs of legs; the first pair of legs is modified to form pincers, shaped to cover the shell entrance when the animal is inside. As the crab grows, it periodically leaves its shell and finds a larger one to occupy. The reddish brown large hermit crab (Pagurus pollicaris; 4–5 in., or 10–12 cm, long) and the small hermit crab (P. longicarpus) are found in North American Atlantic coastal waters.

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or eremite

Individual who shuns society to live in solitude, often for religious reasons. The first Christian hermits appeared in Egypt in the 3rd century AD, escaping persecution by withdrawing to the desert and leading a life of prayer and penance. The first hermit was probably Paul of Thebes circa AD 250. Other famous hermits included St. Anthony of Egypt, who established an early form of Christian monasticism in the 4th century, and the pillar hermit Simeon Stylites. The communal life of monasteries eventually tempered the austerities of the hermit's life. In Western Christianity the eremitic life died out, but it has persisted in Eastern Christianity.

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(born circa 1050, probably Amiens—died July 8, 1115, Huy, Flanders) French ascetic and one of the most important preachers of the First Crusade. A charismatic ascetic, he preached widely in Europe in support of the First Crusade and led his enthusiastic followers to Constantinople in 1096. They advanced to Nicomedia, but Peter was unable to maintain discipline; he returned to Constantinople to ask for help from Alexius I, and in his absence his army was annihilated by the Turks. Peter reached Jerusalem in 1099 and afterwards returned to France, where he became prior of an Augustinian monastery.

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