264 



ai $attiral ^t 



brushes ; its flight is rapid, it mounts high ! the surface, and the Gnat quickly emerges 



in the air, and flics off to a distance with an 

 i extremely rapid horizontal and even mo- 

 tion. The song is rather remarkable, being 

 commenced with a single note slowly drawn 

 i out, and followed by a quick repetition of a 

 j double note, repeated several times in suc- 

 i cession, and mostly uttered when the bird is 

 i perched on the topmost branch of a tree. It 



from its confinement. A warm, rainy season 

 is most favourable to the evolution of Gnata ; 

 and, in such summers, particular districts in 

 most countries are occasionall 

 them in countless swarms 

 who inhabit the more favoured regions of 

 the European continent can hardly conceive 

 hat torments are endured from them in 



nally pestered by 

 . Those persons 



n exceedingly active bird among the I some parts of the world ; but of all people 



I branches, gracefully clinging about and 

 around the flowers of the Eucalypti in search 

 ! of food. It builds in some low bush or 

 i scrubby plant, near the ground, the nest 

 ; being of a compact cup-shaped form, con- 

 structed of dried grasses, and lined with soft 

 ! wool. The eggs are rather large, and often 

 much lengthened ; sometimes quite white, 

 ; but more generally blotched with large 

 ! marks of chestnut-red. It feeds on the pol- 

 1 len of flowers and insects. 



GLTPTODON. The name given to an 

 extinct quadruped, of gigantic dimensions, 



which, like the Armadilloes 

 day. was covered with a tes 



the present 

 elated bony 



armour. In size it was equal to the Rhino- 

 ceros. Prof. Owen has published an elabo- 

 rate memoir on it, which is beautifully il- 

 lustrated. The fine specimen in the College 



" ~ its 



dimensions, curious characters, and state of 

 preservation. It was found in South Ame- 

 rica. 



GNAT. (CulKX.) The Culicidce, or Gnat 

 tribe, are a family of Dipterous insects, whose 

 mouths are furnished with bristly stings, in- 

 cluded in flexile sheaths. Some of the spe- 

 cies are extremely troublesome, as they 

 pierce the skin to feed upon the blood, and 

 at the same time inject an irritating poison- 

 ous fluid. Their flight is accompanied by a 

 humming noise, occasioned by the vibration 

 of their wings : they seldom appear in the 

 day-time, except in thick woods, and they 

 abound in moist situations, which is easily 

 accounted for by their larvae being inhabit- 

 ants of the water. In this state they are 

 very active, swimming with great agility, 

 and often descending ; but coming to the 

 surface to breathe, which they do head down- 

 i wards, the respiratory orifice being at the 

 I end of a very prolonged spiracle arising from 

 I the end of the abdomen. That well-known 



the Laplanders appear to be the greatest 

 sufferers ; for during the heats of their short 

 summe_r, the Gnats fill the air witli such 

 swarming myriads, that the poor inhabitants 

 can hardly venture to walk out of their 

 cabins, without having first smeared their 

 hands and faces with a composition of tar 

 and cream, which is found by experience to 

 prevent their attacks. 



A very small black Gnat ( CuJex reptam>\ 

 with transparent wings, and the legs marked 

 by a white bar, is particularly troublesome 

 in marshy districts during the evening, by 

 its creeping motion on the skin of the face, 

 &c. 



To the above we may add, that the MOS- 

 QUITO (Culex mosquito}, so much dreaded by 

 all who visit the West Indies and America, 

 where its bite seems to operate with peculiar 

 malignity, is a species of Gnat which derives 

 



side with a pair of antennae-like jointed pro- 

 cesses ; the thorax large and angular ; the 

 body suddenly lessening from this part, and 

 continuing of nearly the same size to the 

 tail, which is abruptly truncated, and tipped 

 with four foliaceous processes. In about 

 fifteen days' time the larvae are full grown, 

 and arrive at the pupa state; the animal 

 then appears to have a rounded form, is 

 very active, and still inhabits the water ; the 

 position of its breathing apparatus, however, 

 is now altered, being situated at the anterior 

 part of the body, and consists of two little 

 tubes, which are applied to the surface of 

 the water for the reception of air. When, 

 ready to assume the perfect state, it rises to 



moister atmosphere. But it is not wonderful 

 that in uncultivated wastes, where the waters 

 stagnate, and the heat of the sun is almost 

 insupportable, that the atmosphere should 

 frequently be filled with clouds of these 

 insects, varying in size from three or four 

 inches in length to a minuteness only dis- 

 cernible by the assistance of a microscope. 

 [See MOSQUITO.] 



GNATHODON. A genus of bivalve 

 shells, of which there is one well- known 

 species, (Gnathodon cu-neatiis), from New 

 Orleans. It is ovate, equivalve, and equi- 

 lateral ; and is known from all other shells 

 by the characters of the hinge, having in 

 one valve, a sharp, angular, notched, car- 

 dinal tooth, and two lateral teeth, the 

 posterior of which is elongated, and the 

 anterior angulated, tortuous, shaped like a 

 jawbone ; in the other valve, two cardinal 

 and two lateral teeth, the interior of which 

 is wedge-shaped. Ligament internal, cunei- 

 form ; muscular impressions two. The name 

 has also subsequently been given to a genus 

 of birds. [See next article.] 



GNATHODON. A genus of birds de- 

 scribed by Sir W. Jardine, from a specimen 

 which belonged to Lady Harvey. From the 

 contour of its beak, which has the upper 

 mandible strongly hooked, as in the Dodo, 

 and the under mandible dee 

 is supposed by Mr. Gould 

 or granivorous ; the beak being expressly 

 adapted to denude palm nuts, or other 

 strongly coated seeds, of their hard outer 

 covering. Mr. Gould considers that it is 

 more nearly allied to the Pigeon tribe (Co- 

 lumbidce) than to any other family ; the 

 form of the body and wings, and the struc- 

 ture of the feathers, indicating this affinity. 

 The only known species, Guathodon strigi- 



leeply notched, it 

 to be frugivorous 



