ACA 



ACA 



demies held their assemblies. It took its 

 name from one Academus, or Ecademus, 

 a citizen of Athens ; as our modern acade- 

 mies take theirs from it. This term was 

 also used metaphorically, to denote the 

 sect of Academic philosophers. See ACA- 

 DEMICS. 



ACADEMT, in a modern sense, signifies 

 a society of learned men, established for 

 the improvement of arts or sciences. 

 See SOCIETY. 



ACJENA, in botany, a genus of the Te- 

 trandria Monogynia class and order of 

 plants. There is but a single species, 

 which is a Mexican plant. 



ACALYPHA, in botany, a genus of 

 plants belonging to the Monoecia Mono- 

 delphia class, and the natural order of 

 Tricoccae, called the Tick-fruit. There 

 are fourteen species : the A. virginica, 

 grows naturally in Virginia, and in Cey- 

 lon: the A. virgata is a native of the warm- 

 est countries, and grows plentifully in Ja- 

 maica ; its leaves resemble those of the 

 annual nettle, and sting as much. Most 

 of the other species are natives of the 

 West Indies. The plants have no beauty 

 to recommend them, and are preserved 

 in some botanic gardens merely on ac- 

 count of variety. 



ACANTHA, among botanists, a name 

 given to the prickles of thorny plants. 



ACANTHA is also used by zoologists for 

 the spines of certain fishes, as those of the 

 echinus marinus, &c. 



ACANTHACEOUS, among botanists, 

 an epithet given to all the plants of the 

 thistle kind, on account of the prickles 

 with which they are beset. 



ACANTHONOTUS, in natural history, 

 a genus of fishes of the order Abdomina- 

 les: the generic character is, body elon- 

 gated, without dorsal fin ; spines several, 

 on the back and abdomen. There is but 

 one species, the nasus, about 30 inches 

 long, a native of the East Indies. Tlie 

 eyes are large, and the nostrils conspicu- 

 ous : the body, which is of a moderate 

 width for about the third of its length, 

 gradually decreases or tapers towards the 

 extremity: both head and body are cover- 

 ed with small scales, and are of a bluish 

 tinge, with a silvery cast on the abdomen: 

 the pectoral fins are brown, and of a mo- 

 derate size : the ventral rather .small, and 

 of a similar colour: the lateral line is 

 straight, and situated nearer to the back 

 than to the abdomen: along the lower part 

 of the back are ten strong but short spines, 

 and beneath the abdomen twelve or thir- 

 teen others, which are followed by asmall 

 anal fin. (See plate I. Ichthyology, fig. 1.) 



ACANTHURUS, in natural history, a 

 genus of fishes, of the order Thoracici, of 

 which the gen. character is, teeth small, 

 in most species lobated: tail aculeated on 

 each side : general habit and appearance 

 like the genus Chaetodon, which see. This 

 genus consists of such species of the Lin- 

 naean genus Chaetodon, as, in contradiction 

 to the principal character of that genus, 

 have moderately broad and strong teeth, 

 rather than slender and setaceous ones : 

 they are also furnished on each side the 

 tail with a strong spine. There are twelve 

 species, of which the principal is A. uni- 

 cornis ; this is the largest of the genus, 

 growingto the length of three feetor more. 

 It is a native of the Indian and Arabian 

 seas, in the latter of which it is generally 

 seen in large shoals of two or three hun- 

 dred each, swimming with great strength, 

 and feeding principally on different kinds 

 of sea- weed. This fish was described by 

 Grew, in his Museum of the Royal Socie- 

 ty, under the name of the Lesser Unicorn 

 fish. Fine specimens are to be found in 

 the British and Leverian museums. 



ACANTHUS, BEAR'S BREECH, or 

 BRANK-URSINE, in botany, a genus of the 

 Didynamia Angiospermia class, and be- 

 longing to the natural order of Personatac. 

 There are ten species : 1. The smooth 

 acanthus, with white flowers, proceeding 

 from about the middle to the top of the 

 stalk, is the species used in medicine un- 

 der the name of Branca ursina, or Brank- 

 ursine. It is a native of Italy, about Na- 

 ples, of Sicily, Provence, and the islands 

 of the Archipelago, and is cultivated in 

 our gardens, and flowers in June and July. 

 Turner (in his Herbal in Hort. Kew.) in- 

 forms us, that it was cultivated in Sion 

 gardens so long ago as the year 1551. The 

 leaves, and particularly the roots, abound 

 with a soft, insipid mucilage, which may 

 be readily extracted, either by boiling or 

 by infusion. Rectified spirit digested on 

 the leaves, extracts from them a fine deep 

 green tincture, which is more durable 

 than that which is communicated to spirit 

 by other herbs. Brank-ursine is seldom 

 or ever used medicinally in this country. 

 But where it is common it is employed for 

 the same purposes to which the Althaea, 

 or marsh-mallow, and other mucilaginous 

 vegetables, are applied among us. In fo- 

 reign countries the cow-parsnip is said to 

 be substituted for it, though it possesses 

 very different properties. The leaves of 

 this species of acanthus accidentallygrow- 

 ing round a basket covered with a tile, 

 gave occasion to Callimachus to invent the 

 Corinthian capital in architecture. 2, The 



