GLOSSARY 379 



Intima (Lat. = innermost), an internal cuticle or internal epithelium. 



Invagination (Lat. in, and vagina, sheath), the ingrowth or inpushing of 

 a hollow organ from without. 



Lamella (Lat. = a small blade), a small flat blade-like organ. 



Lamina (Lat. =a plate or blade), a thin flat firm layer. 



Larva (Lat. = a ghost), the term applied biologically to any stage in the life 

 of an animal which differs from the final or mature form to such an extent 

 that a complicated change, or metamorphosis, is necessary to pass from the 

 one to the other. 



Leucocytes (Gr. Aeu*co's, white; K.VTOS, cell), colourless or white blood 

 corpuscles. Their function is to seize and carry off impurities; hence they 

 are also called phagocytes (Gr. $ayeu/, to devour). 



Lower Layer, see Germinal Layers. 



Lumen (Lat. = an opening), the internal canal of a hollow organ. 



Mesenteron (Gr. fiea-os, middle; evrtpov, the gut), that part of the gut 

 formed from endoderm the mid-gut. 



Mesoderm, see Germinal Layers. 



Metamorphosis, see Larva. 



Micron (Gr. piKpos, small), one-thousandth part of a millimetre Denoted 



b y/*- 



Miocytes (Gr. peicov, smaller; KVTOS, cell), the smaller (oat-shaped) cor- 

 puscles found in the blood of Insects. 



Moniliform (Lat. monile, a necklace), like a string of beads. 



Nucleus, see Cell. 



Nymph (Gr. vvpfyr), maiden, nymph, pupa of a moth), the term very 

 unsuitably applied to the aquatic larvae of certain Insects, including Dragon- 

 flies. 



Ocellus (Lat. =a small eye), a simple eye. 



Oesophagus, the gullet. 



Ommatidium (Gr. o^fiariov, a little eye), one of the elongated separate 

 elements of a Compound Eye. 



Ontogeny (Gr. OVTOS, a being), the study of the development and growth of 

 the individual animal. 



Palaeontology (Gr. iraXaios, ancient), the study of extinct animals. 



Papilla (Lat. =a teat), a small elevation like a teat or the finger of 

 a glove. 



Phylogeny (Gr. <pv\ov, the race, tribe), the study of the descent or pedigree 

 of the various tribes of animals. 



Plasma (Gr. ir\a<rp.a, anything moulded), what remains of the blood when 

 the corpuscles are taken away the serum, or liquid part, + the fibrin. 



Pleura or pleurites (Gr. ir\vpa, ribs, side), lateral sclerites or parts of the 

 exoskeleton. 



Podites (Gr. novs, foot), the separate pieces of a jointed appendage of the 

 Arthropoda. Of these, the basal piece is called the protopodite, the inner 

 distal piece endopodite, and the outer distal piece exopodite. 



