Sect. XVI. 15. 1. OF INSTINCT. , 3S 



their own length out of the water, expecting to get Into the 

 trough above. 



This evinces that the ftorge, or attention of the dam to pro- 

 vide for the offspring, is ftrongly exerted amongft the nations 

 of fifh, where it would feem to be the mod neglected ; as thefe 

 falmon cannot be fuppofed to attempt fo difficult and dangerous 

 a tafk without being confcious of the purpofe or end of their en- 

 deavours. 



It is further remarkable, that mod of the old falmon return 

 to the fea before it is proper for the young fhoals to attend them, 

 yet that a few old ones continue in the rivers fo late, that thej 

 become perfectly emaciated by the inconvenience of their fitu- 

 ation, and this apparently to guide or to protect the unexperi- 

 enced brood. 



Of the fmaller water animals we have ftill lefs knowledge, 

 who neverthelefs probably pofTefs many fuperior arts ; fome of 

 thefe are mentioned in Botanic Garden, P.I. Add. Note XXVII. 

 and XXVIII. The nymphx of the water-moths of our rivers, 

 which cover themfelves with cafes of flraw, gravel, and fheli, 

 contrive to make their habitations nearly in equilibrium with 

 the water j when too heavy, they add a bit of wood or firaw j 

 when too light, a bit of gravel. Edinb. Tranf. 



All thefe circumflances bear a near refemblance to the delib- 

 erate actions of human reafon. 



XV. We have a very imperfect acquaintance with the vari- 

 ous tribes of infects : their occupations, manner of life, and even 

 the number of their fenfes, differ from our own, and from each 

 other •, but there is reafon to imagine, that thofe which poiTefs 

 the (enie of touch in the mod exquifite degree, and whole oc- 

 cupations require the mod conftant exertion of their powers, 

 are endued with a greater proportion or knowledge and inge- 

 nuity. 



The fpiders of this country manufacture nets of various 

 forms, adapted to various fituations, to arreft the flies that are 

 their food ; and fome of them have a houfe or lodging-place in 

 the middle of the net, well contrived for warmth, fecurity, or 

 concealment. There is a large fpider in South America, who 

 conftructs nets of fo ftrong a texture as to entangle fmall birds, 

 particularly the humming bird. And in Jamaica there is an* 

 other fpider, who digs a hole in the earth obliquely downwards, 

 about three inches in length, and one inch m diameter \ this 

 cavity {he lines with a tough thick web, which when taken cut 

 refembles a leathern purfe : but what is mod curious, this houfe 

 has a door with hinges, like the operculum of fome fea (hells $ 

 and herfclf and family, who tenant this neft. open and ihut the 



•ic 



v*$ 



