468 GLOSSARY. 



INVER'TEBRATE, without vertebrae. The term is applied to all 



those animals which in common language are destitute of a 



skull and backbone. 

 IRIDES'CENT, having colours like the rainbow. Lat. iris, the 



rainbow. 



ISOLATED, detached. Italian, isola. Lat. insula, an island. 

 LA'BIUM, in entomology, the lower lip. The labial palpi in 



insects are the feelers attached to tne lower lip. 

 LA'BRUM, in entomology, the upper lip. 

 LAGOON, a term applied to a small lake or pond of water; the 



word is derived from the Spanish laguna. Lat. lacuna. 

 LAMELLA, Lat. a thin plate or scale. 

 LAMELLIBRANCHIA'TA, a class of mollusca including the Oyster 



and other well-known Bivalves, in which the gills are in the 



form of membranous plates. 



LARVA, the caterpillar state of an insect. Lat. larva, a mask. 

 LARYNX, in the higher vertebrate animals, the organ of voice, 



situated at, the upper portion of the windpipe. 

 LENS, properly a small roundish glass, shaped like a lentile or 



bean. Lat. lens, a bean or lentile. The word is applied to 



both concave and convex glasses. 

 LEPIDOPTERA, an order of insects to which the Moths and 



Butterflies belong. The wings are covered with a mealy 



substance composed of minute scales. Gr. lepis, a scale, 



and pteron, a wing. 



LIGAMENTS, the bonds or organs by which the various articu- 

 lations of the body are held together. Lat. ligamentum, a 



band or tie. 

 LOBES, the rounded divisions on the edge of a leaf, and applied 



to portions of the animal frame of a similar form. 

 LOCOMOTION, the act of moving from place to place. Lat. locus, 



a place, and motio, a moving. 

 LOPHOBRANCHII, an order of fishes, in which the gills are 



arranged (as in the Pipe-fishes) in small tufts. Gr. lophos, 



a crest, and branchice, gills. 

 MACROURA, a section of ten-footed Crustacea, distinguished (like 



the Lobster and Cray-fish) by the length of the tail. Gr. 



makros, long; and our a, a tail. 

 MAGNESIAN LIMESTONE, limestone which contains a portion of 



the earth magnesia. 

 MALACOPTERYGII, one of the great sections into which the 



osseous fishes are divided. The rays of the fins are soft, 



and in general branched. Gr. mala/cos, soft, and pteryx, a 



wing. It is subdivided into three orders, Abdominales, Sub- 



brachiales, and Apodes. 

 MAMMALIA, the class of vertebrate animals: it includes all those 



that suckle their young. Lat. mamma, a teat. 

 MAMMIFEROUS, having breasts or teats for the nourishment of 



the young by means of milk. Lat. mammai, teats; and fero, 



I bear. 

 MANDIBUL^J, or MANDIBLES, organs for chewing. Lat. mando, 



I chew. Applied to the upper jaws of insects 



