AUGITE AURANTIACE^E. 



247 



the second ; whereas in the Adimonia: they are nearly 

 equal. In the latter genus are comprised two beau- 

 tiful British species, the Chrysomcla Aim of Linnaeus, 

 which is very rare, and the Chrysomcla halcnsis, a very 

 common species on various plants: it is about a 

 quarter of an inch long, of a golden green colour, with 

 the thorax yellow, and the legs brown. 



AUGITE. A mineral which derives its name from 

 a Greek word, indicative of its lustrous character. 

 There are four distinct species of augite, viz. the 

 oblique-edged, the straight-edged, the prismatoidal, 

 and the prismatic augite. 



Fig. 1. 



Fiff. 2. 



Fig. 3. 



The foliated augite, which occupies a prominent 

 place in the first species, is of a dark green colour. 

 The form of its primary crystal is a four-sided prism. 

 One of its secondary crystals is shown at fig. 1, con- 

 sisting of a six-sided prism. Another form is ex- 

 hibited at fig. 2, in which it assumes the character of 

 an eight-sided prism, bevelled on the extremities. 

 i ; ig. 3 is also an eight-sided prism, in which the 

 obtuse terminal edges of two opposite planes meeting 

 under acute angles are truncated. This form of 

 augite occurs in secondary trap-rocks, and in lava as 

 well as in basalts. This mineral is principally distin- 

 guished by its strong internal lustre, and peculiarly 

 marked crystallisation. 



As augite is sometimes mistaken for basaltic horn- 

 blende, it may be advisable to state their respective 

 characteristic distinctions. Augite is, as we have al- 

 ready stated, of a greenish black colour, while basaltic 

 hornblende is invariably of a much deeper black ; it 

 is also softer than augite. Another very peculiar 

 characteristic of hornblende is that it can readily be 

 fused by the agency of the blow-pipe : augite, on the 

 ^contrary, is very difficultly fusible. 



The varieties of this mineral, which are very 

 numerous, and possess great interest in a scientific 

 point of view, will be fully described in their alpha- 

 betical order. 



AULOPUS " pipe-fin," in allusion to the large 

 external rays of the abdominals. A genus of soi't- 

 finned fishes, with abdominal fins, belonging to the 

 salmon family, and combining in rather a singular 

 manner some of the characters of the salmon and 

 some of those of the cod. There is but one known 

 species, the Salmo filamcntosus of Bloch, so called 

 from the filaments or beard resembling those of the 

 cod. The gape is wide, and extends far backwards. 

 The intermaxillary bones, the palate, the edge of the 

 vomer, and tho lower jaw, are furnished with one 

 even row of recurved teeth ; but the tongue is smooth, 

 and the flat part of the palate is without any. The 

 maxillary bones are large, but without any teeth. 

 The abdominal fins are placed immediately under the 

 pectorals, having their external rays very large, so 

 that they seem forked. The first dorsal fin occupies 

 a portion of the back, answering to the anterior half 

 of the distance between the abdominal fin and the 

 anal. They have twelve rays in the gill-flaps. Their 



bodies, cheeks, and gill-lids are covered with large 

 scales, something similar to those of the salmon. In 

 the spawning time they frequent the banks and 

 shallows, but it does not appear that they ascend the 

 rivers. 



AULOSTOMA " pipe-mouth." A genus of 

 spinous-finned fishes belonging to Cuvier's fifteenth 

 and last natural family of the order Bouchcs en flute, 

 which of course has the same meaning as the name of 

 this genus. The fishes of this curiously formed family, 

 which are known to English sailors by the common 

 name of " pipe-fish," without regard to the generic 

 distinctions, form only four genera, and the species 

 are not numerous. They are all natives of the 

 warmer seas, but one species at least is found in the 

 Mediterranean. The distinguishing character of the 

 family is the mouth lengthened into a sort of tube or 

 pipe. There are two divisions, Fistularia, in which 

 the body is long and slender ; and Ccntriscus, in which 

 it is oval and compressed. Aulostoma belongs to the 

 first division ; but neither the tube nor the body is so 

 long in proportion, as in the other genus of that 

 division, Fistularia. 



Aulostoma has several free spines in front of the 

 dorsal ; the body very scaly but slender, though it is 

 enlarged and compressed in the portion between the 

 dorsal and the anal fins. This enlarged portion is 

 followed by a short and slender tail, which terminates 

 in a caudal fin of the ordinary shape. The air-vessel is 

 uncommonly large for the size of the fish. There is 

 but one species, a native of the Indian seas. 



AURANTIACE^E the orange tribe. A natural 

 order of plants, the thirty-seventh of the Jussieuan 

 system, containing about a dozen genera, and be- 

 tween thirty and forty species. The name Hes- 

 perideeE is also applied to this order. The essential 

 botanical characters of the family are, calyx 

 pitcher or bell-shaped, short, from three to five 

 toothed, withering ; petals varying in number from 

 three to five, broad at the base, sometimes distinct, 

 sometimes united ; stamens equal in number with 

 the petals, double or triple ; filaments compressed 

 below ; ovary many-celled, ovate ; one rounded style ; 

 fruit many-celled, the cells filled with pulp, enclosed 

 in little bags, and surrounded by a thick rind, which 

 abounds in glands containing volatile oil. The plants 

 belonging to this order are beautiful evergreen trees 

 or shrubs almost exclusively natives of the East 

 Indies, whence they have been introduced into 

 different parts of the world. Their thick leaves 

 articulated with the petiole, and furnished with 

 pellucid dots containing an essential odoriferous oil, 

 are their obvious peculiarities. Their flowers are 

 generally white and fragrant, their wood hard and 

 remarkably compact, and they produce a fleshy edible 

 fruit containing an acid pulp. Many of them are 

 prized both on account of their medicinal qualities 

 arid the esculent fruits which they yield. In general, 

 their properties are aromatic, stimulating, and re- 

 frigerant. 



The orange, lemon, lime, and citron, may be men- 

 tioned as examples of this order. Of the Citrus 

 aurantium, or orange, there are several varieties, the 

 chief of which are the sweet or China orange, and 

 the bitter or Seville orange. The latter is the variety 

 used in medicine, and ordered in the pharmacopoeias. 

 The orange originally came from Asia, but is now 

 cultivated in Italy, Spain, Portugal, and the warm 

 regions of Europe, as well as in the West Indies. It 



