ASTARTE. 



ASTR.EA. 



330 



crawfish. Lobsters, in common with most of the Crustaceans, have 

 the power of reproduction to a great extent. If a claw be torn off, it 

 is renewed; and if it be injured, the animal will sometimes throw 

 it off by an effort. It seems that any violent shock to the nervous 

 system will cause this act. If a lobster be thrown into boiling water, 

 it will generally throw off its large claws on the instant ; and the 

 same effect has been produced by plunging the animal, when in full 

 life, into spirit. Pennant goes so far as to make them out to be veiy 

 nervous subjects indeed. " Lobsters," says he, " fear thunder, and 

 are apt to cast their claws on a loud clap. I am told they will do 

 the same on firing a great gun ; and that when men-of-war meet a 

 lobster-boat, a jocular threat is used, that if the master does not sell 

 them good lobsters they will salute him." 



That the lobster was well known to the ancients appears from the 

 reference in Mr. Travis's letter, and from many other evidences. It 

 will be sufficient to add that, under the name of atrroKiy, Aristotle, in 

 the second chapter of the fourth book of his 'History of Animals,' 

 gives a most faithful and elaborate account of the species which is still 

 an inhabitant of the Mediterranean. 



Atacu jtui-iatUis, the Crawfish, is to be found in the fresh waters 

 of Europe and the north of Asia. It thrives best in rivers, where 

 in holes in the banks and under stones it lies in wait for the small 

 molluscous animals, little fishes, the larvce of insects, and decomposing 

 animal substances, which form its prey. iDesinarest says that it will 

 live for upwards of 20 years, and that it becomes large in proportion 

 to its age ; that towards the end of spring it casts off the pieces 

 which form its shell, and some days after becomes covered with a 

 crust as solid as the former one, but larger, sometimes by as much as 

 one-fifth. The eggs, which are excluded about two mouths after 

 impregnation, are collected under the lower part of the body or tail, 

 as it U popularly called, after the manner of the hen-lobster. From 

 these proceed the young crawfishes, which are very small and soft, 

 but which bear an exact resemblance to the parent, under whose tail 

 they are nursed for several days. 



The crawfish is taken either by nets or by bundles of thorns in 

 which flesh in a state of decomposition is placed. It is also taken by 

 inserting the hand into the hole which it inhabits ; and at night it is 

 caught by means of lighted torches. [CKUSTACEA.] 



ASTA'RTE, a genus of Concldferout Molluca, with two muscular 

 impressions and a simple mantle-line. The hinge has two divaricated 

 teeth in the right-hand valve ; in the other, one distinct and one 

 obsolete tooth, and the rudiment of a lateral tooth. The ligament ia 

 external 



The species consist of some of the Veneret of Montagu, one of 

 which i a Crastina. (Lam.) Some of them are English shells, and 

 they are generally found on the sandy mud of coasts at a depth which 

 ranges from near the surface to ten fathoms. 



The Crag, the Green-Sand, and some of the old fossiliferoua beds 

 afford many species. 



A'STER, a genus of plants belonging to the natural order Composite, 

 and comprehending a great multitude of species scattered over all 

 parts of the world, especially North America and Australia. Many 

 of them are handsome herbaceous plants, others are small-leaved 

 shrubs, and the remainder are mere weeds. (Nees von Eseubeck, ' Genera 

 et Species Asterearum.') 



Although the number of species of this genus is very great, none 

 of them are of any use to man. A large number are cultivated, 

 and we are indebted to their very handsome flowers for some of the 

 greatest ornaments of our gardens at the latter end of summer. 

 One of the species, After Tripolium, is a British plant. It is very 

 common in muddy salt marshes. It has a stem from 1 to 2 feet high, 

 v.-hHi is erect, hollow, leafy, and many-flowered. The flowers are 

 yellow in the disk and lilac in the circumference. Sometimes the 

 latter are wanting. 



ASTEKACA'NTHUS, a genus of Fossil Placoid Fishes, including 

 :ve British species, from the Oolitic and Lias Formations. (Agassiz.) 



ASTERI'AD^E, a family of the order Echinodermata including the 

 tru.- Star-Fishes. This family is distinguished from the rest of the 

 i.r.l.T by the body being more or less lobed, and the lobes channeled 

 beneath for cirrhi, which act aa suckers and are the organs of motion. 

 >r E. Forbes in his 'History of British Star-Fishes' has 

 arranged the British species of this family under four heads : 



1. The Uratterice, Stellate Star-Fishes with rounded arms and four 

 ranges of suckers in each avenue. Of this family there is only one 

 genus Uraster, inhabiting the British coasts. Of this there are four 

 species U. glacialii, U. rubens, U. violacea and V. hispida. 



2. The Solatteriff, also stellate (sometimes multi-radiate), with 

 rounded anus, but only two ranges of suckers in each avenue. To 



ibe belong the genera Cnbelia and Solatter of which C. ocidata, 

 C. roita, S. endeca, and S. pappota inhabit the British coasts. 



:;. itnHi''i,:'erite, which are pentagonal and havetwo ranges of suckers. 

 The British genera of this tribe are AtlL-rina, Palmifiee, and Goniaster. 

 The species are A. yibbma, P. memltranaceus, G. Tcmjiletoni, and 6'. 

 trii. 



4. Asliriie, Stellate Star-Fishes with the upper surface of the body 

 flat. It includes the British genera Ailerita and Luidia. Each of 

 these have one species, A. aurantiaca and L. frayiliteimj. [EcuiNo- 

 DK8MATA. 



I 



Asterias tesseltita. 



ASTE'RIAS (Lam.), a genus of Radiated Animals widely diffused 

 over the seas. The Linnsean genus comprises every form of radiation 

 which appears in the tribe, but the genus Asterias of Lamarck 

 includes only the Star-Fishes properly so called. These are divided 

 into two sections, 'the Scutellated Star-Fishes,' and 'the Radiated Star- 

 Fishes.' The former have an angular body, the lobes or rays of which 

 are short, their length not exceeding the diameter of the disk : the 

 latter have a body furnished with elongated rays, whose length far 

 exceeds the diameter of the disk. The following is a general description 

 of the animals to which the name Aateria* has been applied : 



Each ray is furnished with a longitudinal furrow on its lower side, 

 and this furrow is pierced laterally with smal^ holes, through which 

 pass the feet or tentacula, which are membranous, cylindrical, and 

 each of them terminated with a little disk, which performs the office 

 of a cupping-glass, somewhat in the same manner as the acetabula or 

 suckers of the cuttle-fishes. By elongating or shortening these 

 numerous little organs, and by fixing them by means of their terminal 

 disks, the progressive motions of the Star-Fish are regulated. The 

 rest of the lower surface is furnished with small moveable spines, 

 which also assist progression. The whole surface is also pierced by 

 pores, through which pass tubes much smaller than the feet, serving 

 probably to absorb the water, and to introduce it into the general 

 cavity, for the purposes of a kind of respiration. A large stomach 

 lies close to the mouth ; and two ramified caeca, each suspended to a 

 kind of mesentery, are given off to each ray, which is also furnished 

 with two ovaries, by means of which the animals are supposed to 

 reproduce their species without the aid of a second individual. A fine 

 cord, which surrounds the mouth and sends a branch to each arm, is 

 considered as the development of their nervous system. [ASTERIAD.E ; 



ECHINODERMATA.] 



ASTERI'NA, a genus of Star-Fishes, including the smallest of the 

 British species, A. yibbosa of Pennant. The Gibbous Starlet has a 

 5-sided body, which is thick and covered above and below with 

 short spines ; the avenues are bordered by a single row of spines, and 

 the suckers are in two rows. De Blainville makes out of this species 

 two, which he calls A shrias minuta and A. pulc/ulla. A. gilbosa is 

 found very generally around the British Islands, and also in the 

 Mediterranean, and on all the shores of Europe. 



ASTEROIDA, a group of Zoophytes, belonging to the A nthozoa 

 or Put iijiifera. [PoLYi'iFERA.] 



ASTEROPHYLLI'TES (Bronguiart), a genus of Fossil Plants con- 

 taining many species ; from the Coal Formations of Europe and America 



ASTEROPTY'CHIUS, a genus of Fossil Placoid Fishes, from the 

 Mountain Limestone of Ireland. (Agassiz.) 



ASTR^EA, a genus of Radiate Animals belonging to the family 



Aatrtra rotulosa. 

 Puli/jiifera. The species are found sometimes incrusting marine 



