Page:The American Cyclopædia (1879) Volume X.djvu/143

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LANCE LANCELOT 137 opens into it ; on the latter it receives Navy Board and Admiralty inlets. It was discov- ered by Baffin in 1616. -LANCE, a weapon. See ARMS. LANCE, George, an English painter, born at Little Easton, near Colchester, March 24, 1802, died June 18, 1864. He studied with Haydon, and first exhibited at the academy in 1828. His favorite subjects were fruit, flowers, game, &c., arranged in picturesque and effective confu- sion, and executed with an elaborateness and a richness of color almost equalling the efforts of the old Dutch masters of still life. Some- times figures are introduced, as in his "Red Cap," in which a monkey is represented pre- siding over a table covered with fruits and festal appointments. He also painted histor- ical and imaginative pieces. He restored a large portion of the celebrated "Boar Hunt" of Velasquez in the British national gallery. LANCELET (branchiostoma or amphioxus), the lowest known of the vertebrate animals, con- stituting the order pharyngdbranchii of Hux- ley, the leptocardia of Haeckel, who regards it as a primary division of the branch of verte- brates. This anomalous fish has been found on the coasts of Great Britain and Sweden, in the Mediterranean, on our southern Atlantic coast, and in the Indian ocean. It is from 1 to 2 in. long, tapering at each end, ribbon-like, translucent, and silvery white; it generally burrows in the sand in deep water, feeding on minute animalcules. Along the back runs a median fin, expanding at the tail into a lancet- shaped caudal ; there are no apparent pectorals and ventrals ; at the lower surface, extending Lancelet (Amphioxus lanceolatus). 1. Upper side. 2. Lower side. 3. Anatomical diagram: A, notochord; B, spinal chord; C, mouth surrounded "by cirrhi ; D, greatly dilated pharynx perforated by ciliated clefts; E, intestine terminating in anua F; G, haemal system. forward from the anal and branchial apertures, are two lateral folds, which led Pallas to re- gard it as a gasteropod mollusk. The mouth is a longitudinal fissure, in the front of the head, without jaws, but surrounded by several car- tilaginous filaments. The mouth opens into a greatly developed pharynx or throat, the walls of which, strengthened by cartilaginous fila- ments, are perforated by transverse slits, the whole covered with a thickly ciliated or fringed membrane ; this is the respiratory sac, the water entering by the mouth, passing between the branchial slits and over the ciliary fringes filled with blood into the abdominal cavity, and escaping by an opening on the lower sur- face in front of the vent (porus abdominalis of Muller). From the branchial sac the intestine, having a liver-like organ attached, extends to an oval aperture under the tail. There is no single contractile cavity or heart, the only ex- ception in vertebrates, the circulation being effected by several contractile dilatations of the great blood vessels, as in the annelids ; the blood is colorless. There is no proper skele- ton ; the vertebral column, moto-chord or chor- da dorsalis, is a semi-gelatinous rod, enclosed in a sheath and supporting the spinal cord, and is composed of 60 to 70 fibrous laminae loosely attached to each other ; there is also a cartila- ginous apparatus supporting the mouth, and 70 to 80 hair-like ribs surrounding the bran- chial cavity. There is no skull, and no ex- pansion of the spinal cord into a brain, though from its anterior extremity are given off nerves tc the rudimentary eyes, and perhaps other nerves of special sense. The arrangement of the muscles is fish-like ; the skin is thin, but tough and scaleless. The location of the re- spiratory system in the anterior portion of the intestinal canal is met with also in the cyclo- stome fishes. This most aberrant form is clear- ly a vertebrate, though it has no brain, and the respiration and circulation of an annelid. It has been believed by some to favor the idea of Kowalewsky and Kupffer, that the ascid- ians show a kinship to the vertebrates, and it certainly has some remarkable invertebrate features found in no other vertebrate animal. The common species is the B. lanceolatum. LANCELOT, Dom Claude, a French grammarian, born in Paris about 1615, died at Quimperle", April 15, 1695. In early life he attracted the attention of Duvergier de Hauranne, the cele- brated abbot of St. Cyran, and through his in- fluence he joined the recluses of Port Eoyal, whom he greatly assisted in the organization and management of their schools. He wrote grammars of the Latin, Greek, Italian, and Spanish languages, and a Grammaire generale et raisonnee, better known as Grammaire da Port Eoyal, which has been frequently reprint- ed. On the dispersion of the society of Port Royal in 1660, Lancelot became preceptor of the duke of Chevreuse's son, and from 1669 to 1672 was attached in the same capacity to the two young princes of Conti. In 1673 he re- tired to the abbey of St. Cyran, where he led a life of austerity; and in 1680 was ordered to Quimperle", where his last years were spent in devotion. Besides his philological works, he left a manuscript memoir of the abbot of St.