GLOSSARY 283 



pupa state of butterflies is often called the chrysalis, that of insects 

 with an incomplete metamorphosis, as the grasshopper, is frequently 

 designated nymph. 



Qucrcus. A highly important genus of trees, order Cupuliferse. There 

 are two varieties of British oaks, Quercus scssiliflora {Robur} and 

 pedunculata. Q. infectoria, from Asia Minor and Turkey, is 

 valuable for its wood, and especially for its galls, from which 

 tannin and gallic acid are derived, used in ink-making and for 

 photographic purposes. Nearly all the cork of commerce comes 

 from a species of the oak (Q. suber) growing in Spain, southern 

 France and Italy, and northern Africa. 



Radicle. The rudiment of the root of an embryo plant. 



Ramification. Division or separation into branches; the issuing or 

 spreading of small vessels from a large one. 



Raptorial. Adapted for seizing prey. 



Regiirgitation. The act of pouring or swallowing back by the same 

 orifice or place of entrance. 



Respiration. The act of breathing. The process by which the blood 

 continually absorbs the gas known as oxygen from the air, and 

 gives off in exchange carbonic acid, thus effecting its purification. 



Respiratory. Pertaining to, or serving for respiration. 



Reticulated. Marked like network. 



Rudimentary. In an imperfectly developed condition. 



Rufescent. Somewhat reddish. 



Rufous. Reddish, of a red-brown colour. 



Sac. A bag or pouch. 



Saliva. The fluid or chief secretion of the mouth ; derived from various 

 glands. 



Salivary. Secreting or conveying saliva. The salivary glands of 

 insects are appendages to the alimentary canal, and open near the 

 mouth. They vary in form and number, and sometimes are not 

 present. In Lepidopterous larvae they constitute the silk glands, 

 and have a distinct opening through the spinneret (which see). 



Segments. The transverse rings of which the body of an insect, and of 

 certain other animals, is composed. Their ring-like nature is best 

 seen in larvae, and in the tail portion of adult insects. In the latter 

 the rings are grouped into three sets or regions, forming the head, the 

 thorax and abdomen. In the larva state this grouping is not distinct. 



Skeleton. The skeleton of an insect is formed of the hardened body- 

 wall or skin, which furnishes support to the softer organs. This 

 hardening is due to the deposition in it of a horny substance 

 termed chitine. 



Species. An assemblage of individuals having structural features in 

 common. 



Specific. That designates the species, or constitutes it. 



Spheroidal. Having the form of a spheroid, i.e., a body approaching 

 to the form of a sphere, or the round. 



Spinneret. A projecting papilla situated within the mouth of many 

 caterpillars, communicating internally with glands which secrete 

 silky material, externally with the outside. Through this organ 



