part ; applied to the antennae of insects 

 when the setigerous joint is not conspicu- 

 ously larger than the preceding one, be- 

 ginning with a narrow base, and growing 

 broader. 



ANNELIDOUS. Belonging or pertaining to 

 the Annelida, a division of the class 

 Vermes. 



ANNULATA. Those invertebrated animals 

 in which the covering or envelope of the 

 body is divided by transverse folds into 

 rings, whose teguments may be either 

 hard or soft, the muscles being situated 

 internally. 



ANNULATE. When a leg, antennae, &c. of 

 an insect is surrounded by a narrow ring 

 of a different colour. 



ANNULATED. Formed of, marked with, or 

 divided into distinct rings. 



ANNULOSE. Furnished with or composed of 

 rings. 



ANOMALIPED. When the middle toe of a 

 bird is united to the exterior by three 

 phalanges, and to the anterior by one 

 only. 



ANOMALOUS. Deviating from a general rule 

 or system ; different from congeneric spe- 

 cies, &c. 



ANOUROUS. Destitute of a tail. 



ANSERINE. Pertaining to the genus Anser ; 

 resembling a goose. 



ANTENJMS. The horn-like processes pro- 

 jecting from the head of insects and crus- 

 taceous animals. In insects they are 

 uniformly two in number, but in Crustacea 

 there are more than two ; and they are 

 composed of small rings successively added 

 to each other till they form a tube, contain- 

 ing nerves, muscles, and air-pipes. In 

 some insects the antennae are very long, 

 in others short. That they are organs of 

 some sense is very evident, and it has long 

 been considered to be that of touch ; hence 

 they have been called feelers: but M. 

 Straus-Durckheim, who paid great atten- 

 tion to this subject, thinks differently, and 

 says, " when observing the various actions 

 of insects, we see them suddenly stretch 

 their antennae forwards in case of noise, 

 danger, or, in general, when anything is 

 done to attract their attention ; and they 

 keep them thus stretched forward as long 

 as their attention continues; a circumstance 

 which proves that the antennae serve the 

 purpose of apprising them of what passes 

 at a distance, and consequently must 

 either be organs of hearing or organs of 

 smell." Other naturalists have made ex- 

 periments which led them to a similar 

 conclusion ; and it is now pretty generally 

 admitted that, instead of being the organs 

 of touch, the antennae of insects are the 

 organs of hearing. But whatever may be 

 the use for which they were designed by 

 nature, they have been employed by en- 

 tomologists as excellent distinctive cha- 

 racters of genera, &c., and are known by 

 various epithets, according to their form 

 and covering ; as, setaceous (bristle-like), 

 when they are long, slender, and taper to 

 the point, without any marked indenta- 

 tion or protuberance; filiform (thread-like), 

 when preserving throughout a uniform 



size and substance ; incrassated, gradually 

 increasing in substance towards the apex ; 

 moniliform (necklace-shaped), each sepa- 

 rate joint -being oval or globose, and the 

 portion connecting it with the next joint 

 very slender ; ensiform (sword-like) ; fusi- 

 form v spindle-shaped) ; anstate (termi- 

 nated by a hair) ; serrate (saw-like) ; den- 

 tate (toothed) : pectinate (comb-shaped) ; 

 ciliate (each joint furnished on each side 

 with a single hair) ;JtabcUate (fan-shaped) ; 

 furcate (fork-like) ; ramose (branched) ; 

 plumose (feathered) ; lamellate (with a 

 plate-like knob) ; pcrfoliate (with a knob, 

 composed of loosely-attached joints) : ver- 

 ticillate (with whorls of hair) ; pilose (co- 

 vered with down) ; setose (furnished with 

 irregular, harsh, bristly hair) j cylindrical, 

 prismatic, &c. 



ANTENNAL. Relating to the antennae of 

 insects. 



ANTENNIFORM. Having the form of or being 

 shaped like antennae. 



ANTERIOR. The fore part ; as the anterior 

 limbs opposed to the posterior. In bivalve 

 shells, the side opposite to that on which 

 the ligament is situated : of a spiral uni- 

 valve, that part of the aperture which is at 

 the greatest distance from the apex : of a 

 symmetrical conical univalve (such as Pa- 

 tella), that part where the head of the | 

 animal lies, indicated by the interruption j 

 of the muscular impression : of Cirripedes, \ 

 that part where the cilia protrude. 



ANTIPERISTALTIC. A term applied to the 

 vermicular contractions of a muscular tube 

 when they follow each other in a reverse ; 

 direction to the usual mode. 



ANTIQUATED. A term in conchology to de- 

 note that a shell is longitudinally furrowed, 

 but interrupted by transverse furrows, 

 as if it had acquired new growth at each 

 furrow ; i. e. each fresh deposit or layer of 

 calcareous matter, forming a new margin, 

 being replaced by its successor, no longer 

 constitutes the margin, and is consequently 

 antiquated (out of date). 



ANTLERED. Furnished with antlers, or 

 branching horns ; as, the head of a stag. 



ANTLIA. The oral instrument of L/epidop- 

 terous insects, in which the ordinary trophi 

 are replaced by a spiral, bipartite, tubular 

 machine for suction, with its appendages. 



ANTORBITAL. Opposite the orbits. 



ANUS. The termination of the rectum 

 In entomology, the last two segments of 

 the abdomen. In conchology, a depression 

 of the posterior side near the hinge of 

 bivalves. 



AORTA. The great artery, or trunk of the 

 arterial system, in animal bodies. It pro- 

 ceeds from the left ventricle of the heart, 

 and gives origin to all the arteries, except 

 the pulmonary arteries. 



AORTAL. AORTIC. Pertaining to the aorta. 



APERTURE. A hole, cleft, or chasm : any 

 opening, as the mouth of a shell, from 

 which the head of the animal protrudes. 

 The aperture, or entrance to the spiral 

 cavity of univalve shells, is composed of 

 the inner lip, or labium, which generally 

 forms the axis of the shell, and the outer 

 lip or labrum, on the opposite side. 



