GLOSSARY. 



35 



a line with the bill, as in divers, &c. 

 pervious, when they are open, and may 

 be seen through from side to side, as 

 in gulls, &c. 



Noted, Belonging to the back. 



Nucleated. Having a nucleus or centra 

 particle; applied to the elementary 

 cells of animal tissues, the most im- 

 portant properties of which reside in 

 the nucleus. 



Nudibrachiata. The Polypes whose arms 

 are not clothed with vibratile cilia. 



Nudibranchiata. An order of Gastero- 

 pods in which the gills are exposed. 



Nummulite. Fossil remains of a cham- 

 bered shell of a flattened form, former- 

 ly mistaken for money. 



Nutrient. Nourishing ; producing growth. 



Nymph. The pupa, or chrysalis; the 

 second state of an insect, passing to its 

 perfect form. 



O. 



Obese. Unnaturally large and distended, 

 as if from disease or too much food. 



Oblique. Running sideways : when the 

 longitudinal line is cut through at acute 

 angles. 



Obliterate. A term in entomology ap- 

 plied to impressions and elevations 

 when almost effaced. 



Oblong. Longer than broad: the longi- 

 tudinal diameter being more than twice 

 the length of the transverse, and the 

 ends varying, dr rounded. 



Oblong-ovate. Between oblong and egg- 

 shaped. 



Obscure. A surface which reflects the 

 light but little. 



Obsolete. Partially indistinct; not well 

 defined; not fully developed; as the 

 joint striae on certain shells. 



Obtruncated. Lopped off; deprived of 

 a limb. 



Obtuse. Blunt ; not pointed or acute ; 

 dull ; obscure : terminating bluntly, 

 but within the segment of a circle. 



Obumbrant. When the scutellum of an 

 insect overhangs the metathorax. 



Obverse. When an object is viewed with 

 its head towards you. 



Occiput. That part of the skull which 

 forms the hind part of the head. 



Ocellated. A term applied to eye-like 

 spots ; formed with the figures of little 

 eyes. 



Ocellus. An eye-like spot in the wings of 

 many Lepidoptera, and consisting of 

 annuli of different colors, inclosing a 

 central spot or pupil. Blind Ocellus is 

 one without the pupil. Spurious Ocel- 

 lus, a circular spot without any defined 

 iris or pupil. Simple Ocellus, when the 

 ocellus consists only of iris and pupil. 

 Compound Ocellus, when it consists of 

 three or more circles. Nictitant Ocel- 

 lus, when the ocellus includes a tumu- 

 lar spot of a different color. Fenestrate 

 Ocellus, when an ocellus has a trans- 

 parent spot. Dioptrate Ocellus, a fenes- 

 trate ocellus divided by a transverse 

 line. Double Ocellus, when two ocelli 

 are included in the same circle or spot ; 

 and when such ocelli join each other 

 they are termed twin ocelli. Sesquial- 

 terous Ocellus, an ocellus with a smaller 

 near it. The simple eyes of insects are 

 small, transparent, semi-globular lens- 

 es, generally three in number, and ar- 

 ranged in a triangle on the crown of 

 the head. Though their use has never 

 been satisfactorily proved, enough has 

 been ascertained for entomologists to 

 agree in considering them organs of 

 vision. The eyes of larvae, spiders, 

 and some other Annulosa are simple 

 ocelli, arranged in groups. They are 

 also called stemmata. 



Ochraceous. Of a dull brownish-yellow 

 c6lor ; approaching to the color of 

 ochre. 



Octodentate. Having eight teeth. 



Octofid. In entomology, separated into 

 eight segments. 



Octonocular. Having eight eyes. 



Octopod. Having eight legs. 



Octoradiated. Having eight rays. 



Oculi (oculus). The eyes of insects are 

 generally composite, i. e. formed of fa- 

 cets or minute lenses, which are hex- 

 agonal, and vary from fifty to twenty 

 thousand in a single eye ; every one of 

 them receiving the image of an object, 

 and appearing to correspond with the 

 crystalline lens of the human eye. 



Oculiform. Shaped like the eye. 



Odoriferous. Diffusing fragrance. 



