GLOSSARY 535 



Inflorescence — ^The mode of arrangement of the flowers of plants. 



Infusoria — A class of microscopic Animalcules, so called from their having 

 originally been observed in infusions of vegetable matters. They con- 

 sist of a gelatinous material enclosed in a delicate membrane, the 

 whole or part of which is furnished with short vibrating hairs (called 

 cilia), bv means of which the animalcules swim through the water or 

 convey the minute particles of their food to the orifice of the mouth. 



Insectivorous — Feeding on Insects. . , . , , 



Invertebrata, or Invertebrate Animals — Those animals which do not possess 

 a backbone or spinal column. 



Lacuna- — Spaces left among the tissues in some of the lower animals, and 

 serving in place of vessels for the circulation of the fluids of the body. 



LamcUated — -Furnished with lamellae or little plates. 



Larva (pi. Larvar) — The first condition of an insect at its issuing from the 

 egg, when it is usually in the form of a grub, caterpillar, or maggot. 



Larvnx — The upper part of the windpipe opening into the gullet. 



Laiircntian — A group of greatly altered and very ancient rocks, which is 

 greatly developed along the course of the St. Laurence, whence the 

 name. It is in these that the earliest known traces of organic bodies 

 have been found. 



Legumiiwscr — An order of plants represented by the common Peas and 

 Beans, having an irregular flower in which one petal stands up like 

 a wing, and the stamens and pistil are enclosed in a sheath formed 

 by two other petals. The fruit is a pod (or legume). 



Lemuridcc — 'A group of four-handed animals, distinct from the Monkeys 

 and approaching the Insectivorous Quadrupeds in some of their char- 

 acters and habits. Its members have the nostrils curved or twisted, 

 and a claw instead of a nail upon the first finger of the hind hands. 



Lepidoptera — An order of Insects, characterized by the possession of a 

 spiral proboscis, and of four large more or less scaly wings. It 

 includes the well-known Butterflies and Moths. 



Littoral — Inhabiting the seashore. 



Loess — A marly deposit of recent (Post-Tertiary) date, which occupies a 

 great part of the valley of the Rhine. 



Malacostraca — ^The higher division of the Crustacea, including the ordinary 

 Crabs, Lobsters, Shrimps, &c., together with the Woodlice and Sand- 

 hoppers. 



Mammalia — The highest class of animals, including the ordinary hairy 

 quadrupeds, the Whales, and Man, and characterized by the produc- 

 don of living young which are nourished after birth by milk from 

 the teats (Mammce, Mammary glands) of the mother. A striking dif- 

 ference in embryonic development has led to the division of this 

 class into two great groups, in one of these, when the embryo has 

 attained a certain stage, a vascular connection, called the placenta, 

 is formed between the embryo and the mother; in the other this is 

 wanting, and the young are produced in a very incomplete state. 

 The former, including the greater part of the class, are called 

 Placental mammals; the latter, or Aplacental mammals, include the 

 Marsupials and Monotrcmcs (Ornithorhynchus). 



Mammiferous — Having mamma; or teats (see Mammalia). 



Mandibles, in Insects — The first or uppermost pair of jaws, which are 

 generally solid, horn}', biting organs. In Birds the term is applied to 

 both jaws with their horny coverings. In Quadrupeds the mandible is 

 properly the lower jaw. 



Marsupials — An order of Mammalia in which the young are born in a very 

 incomplete state of development, and carried by the mother, while 

 sucking, in a ventral pouch (marsupium), such as the Kangaroos, 

 Opossums, &c. (see Mammalia). 



Maxilla:, in Insects — The second or lower pair of jaws, which are composed 

 of several joints and furnished with peculiar jointed appendages called 

 palpi, or feelers. , , , r i • 



Melanism — The opposite of albinism; an undue development of colouring 

 material in the skin and its appendages. 



