popular Sh'ctumarg of gmmatcfc $atur*. 699 



animals for their own abodes, those cylin- 

 drical retreats lined with silk and fitted to 

 the size of the creature's body, are amongst 

 the most ingenious. These are of two kinds : 

 1st, those which are movable, the creature 

 generally weaving various extraneous mate- 

 rials into the texture of the web, and often 

 with the greatest regularity (amongst which 

 I may particularly mention the nests made 

 by the caddice-worms and the caterpillars 

 of various Lepidoptera) ; and 2ndly, those 

 which are fixed, being formed either in wood 

 or the earth. Instances of the latter are 

 afforded by various species of wild bees and 

 wasps, but they are of a comparatively rude 

 construction compared with the cells of the 

 Trap-door Spider. The interest excited by 

 the accounts of these Spiders has been kept 

 alive since the middle of the last century, 

 when M. Sauvages published his account of 

 an " Araicjni'f tnaconne (IMygale ccementaria) 

 in the Memoirs de 1' Academic des Sciences, 

 for 1758." The writer then gives several 

 instances of specimens having been described 

 and published in various scientific works 

 since that date ; and proceeds to quote the 

 description of one first given in Brown's 

 History of Jamaica. " Tarantula 2. The 

 black Tarantula (Cteniza nidulcm*). The 

 valves of the nest are so well contrived, and 

 so strongly connected, that whenever they 

 are forced open, the native elasticity of the 

 ligaments that fix them restore them imme- 

 diately to their usual position. It is most 

 frequent in the loose rocky soils, and 

 nestles under ground." Mr. W. adds, by 

 way of a note, " Brown's figure represents 

 the regular trap -door partly opened, having 

 a larger and looser flap attached to its base 

 at the hinge above, and falling backwards ; 

 and a specimen of the nest in the Linnacan 

 Society's collection is furnished with a short 

 lax membranous appendage on the outside 

 of the trap-door immediately behind the 

 hinge." 



Another species (Mygale Tonica) is de- 

 scribed by Sydney Smith Saunders, Esq., 

 who noticed a number of nests during a short 

 excursion to Zante. These nests were found 

 close round the roots of the olive-trees in a 

 somewhat elevated situation, and were ge- 

 nerally observed two or three together about 

 the same tree : the soil a sort of sandy clay, 

 of a light ochraceous colour. " The upper 

 portion of the nests was slightly raised above 

 the surface of the ground ; but this may 

 have arisen from the washing away of the 

 surrounding earth during the heavy au- 

 tumnal rains, the more especially as from 

 the coating of moss which showed itself in 

 many cases upon the upper surface of the 

 operculum, they could not have been of very 

 recent construction. The form and struc- 

 ture of the opercula were also peculiar, all 

 of them being more or less provided with an 

 elevation of the posterior margin directly 

 above the hinge, to the extent in some in- 

 stances of one- third of the diameter of the 

 lid. The object of this projection could not 

 be mistaken, for, acting as a lever, the 

 slightest pressure upon it would suffice to 

 raise the operculum, and afford the readiest 

 ingress. This elevation appears to be pro- 



duced by a gradual lengthening in the di- 

 rection of the hinge of the respective layers 

 of which the lid is composed. * * * The in- 

 terior lining of the tube of M. lonica appears, 

 from all the nests which I have seen, to be of 

 a less perfect consistency than that of M. fo- 

 dienf, and divested of that circumference of 

 macerated earth, or exterior wall, of a more 

 olid consistency than the surrounding mass, 

 which in those of the last-mentioned species 

 give strength to the work, and facilitate the 

 separation of the tubes from the mass in 

 which they are imbedded. In attempting 

 such separation, the tubes of the Zante 

 Ml/gale invariably broke asunder, although 

 this effect may be in some measure attri- 

 buted to the excessive dryness of the earth 

 at the time of excavation. The length of 

 these tubes was about four and five inches." 

 We now return to Mr. Westwood's obser- 

 vations on the species of Trap-door Spiders, 

 to notice one which he names Actinvpu* 

 cediJKatorius. " This Spider is of a pitchy 

 black colour, and (with the exception of the 

 abdomen) very shining and polished ; the ' 

 abdomen (which is considerably larger than 

 the cephalo-thorax and greatly elevated and 

 gibbose) is obscure, very finely sericeous, and 

 of an uniform dull brown black colour : the 

 legs are clothed with hair and fine bristles 

 of various lengths, and the various joints 

 are connected together by a very pale 

 whitish membrane, which gives them the I 

 appearance of l>eing annulated ; these limbs 

 are nearly of equal size, but variable in , 

 thickness ; the palpi are also of considerable 

 length, and have all the appearance of a 

 pair of feet, at least in the female, which is 

 the only sex I have seen either of this or the 

 Jamaica species. This species is a native of 

 North Africa, where it was discovered by 

 Mr. Drummond Hay. The nests are about 

 four inches deep, slightly curved within, and 

 three-quarters of an inch in diameter ; the 

 valve at the mouth not being circular, but 

 rather of an oval form, one side, where the ! 

 hinge is placed, being straighter than the 

 other. The valve is formed of a number of 

 layers of coarse silk, in the upper layers of 

 which are imbedded particles of the earth, 

 so as to give the cover the exact appearance 

 of the surrounding soil, the several succes- 

 sive layers causing it, when more closely 

 inspected, to resemble a small flattened 

 oyster-shell. The mouth of the nest is 

 shelved off at the edge, so that the valve, 

 which is also shelved off at the edge, falls 

 into and upon the orifice, and shuts it far 

 more completely than if the edges of the 

 valve had been cut straight. The inner 

 lining of the nest and of the valve is pure 

 white. 



TREE-FROG. [See HTLA.] 



TREPANG. (HoJotAuria ed7w.) A 

 marine Radiated animal, belonging to the 

 genus Holothuria; sometimes called the Sea 

 Cucumber, which is said to be so abundant 

 in certain parts of the Australian coasts, 

 that by diving for them, in from three to 

 eight fathoms water, a man will bring up 

 eight or ten at a time. The mode of pre- 

 serving it is this : the animal is split down 



