USED IN ENTOMOLOGY. 



93 



Orbit: an imaginary border around the eye: in Diptera the orbits are divided 

 into vertical or superior ; frontal and facial or anterior ; of the cheek or 

 inferior : occipital or posterior. 



Orbital sclerite: a narrow sclerite encircling some eyes. 



Order: one of the primary divisions of the Class Insecta, based largely on 

 wing structure and then usually ending in -ptera. 



Ordure: excrement; usually applied to such as is foul or offensive. 



Orichalceous: ^ aurichalceous ; q. v. 



Oriental: in geographical zoology as used by Wallace, that part of the earth's 

 surface including Asia east of the Indus River, south of the Himalayas and 

 the Yangtse-kiang watershed, Ceylon, Sumatra, Java and the Philippines. 



Orificium: the anal or genital opening. 



Original type: is the actual specimen from which a published description is 

 prepareel. 



Orismologia -y: the defining of scientific or technical terms. 



Orthoptera: straight winged: an ordinal term applied to insects in which the 

 primaries are not used in flight, but cover the longitudinally folded secon- 

 daries ; mouth mandibulate ; head set into prothorax, the latter free ; meta- 

 morphosis incomplete. 



Orthorrhapha: that section of Diptera in which the pupa escapes from larva! 

 skin through a T-shaped opening on back : see cyclorrhapha. 



Orthorrhaphous : straight-seamed. 



Os: the mouth of insects, in general. 



Oscillation: a vibrating or swinging from side to side. 



Osculant: intermediate in character between two groups or series. 



Usmaterium -la: flashy, tubular, eversible processes prodvicing a penetrating 

 odor, capable of being projected through a slit in the prothoracic segment of 

 certain Papilionid caterpillars, and from openings elsewhere in the bodies of 

 other forms. 



Osmosis: the tendency of liquids to pass or diffuse through a membrane or 

 septum. 



Osselet: ^ossicle; q. v. 



Ossicle: a small nodule of chitin resembling a bone. 



Ossicula: small corneous pieces that serve in the articulation of the wings 

 to the thorax. 



Ostia: the slit-like openings of the heart. 



Ostiolar canal: a marginal furrow leading from the ostiole. 



Ostiole: in Heteroptera, the openings at the sides of meso- and meta-thorax, 

 through which an odoriferous fluid is excreted. 



Ostium: singular of ostia; q. v. 



-OSUS; an affix, signifying saturation, or the possession of the quality ex- 

 pressed in the stem word. 



Otocyst: an auditory or ear-like vesicle. 



Otolith: a little ear-loone : granules or concretions found in an otocyst. 



Outer lobe: of maxilla = galea : q. v. 



Outer margin: the outer edge of wing, between ape.x and hind angle. 



Ovo, Ovum: the eggs; an egg. 



