1832J BOTANIC GARDEN. 81 



When we v\'erc at Bahia, an elator or beetle (Pyrophojus lu- 

 minosus, Illig.) seemed the most common luminous insect. The 

 li^lit in this case was also rendered more brilliant bv irritation. 

 I amused myself one day by observing tiie springing- powers of 

 tiiis insect, wliich have not, as it appears to me, been properly 

 described.* Tlie elater, wlien placed on its back and prepaiing 

 to spring, moved its head and thorax backwards, so that Ihe 

 pectoral spine was drawn out, and rested on the e(]ge of its 

 sheath. The same backward movement being continued, the 

 spine, by the full action of the muscles, was bent like a spring ; 

 and the insect at this moment rested on the extremity of its head 

 and wing-cases. The effort being suddenly relaxed, the head 

 and thorax flew up, and in consequence, the base of the wing- 

 cases struck the supporting surface with such force, that the 

 insect by the reaction was jerked upwards to the height of one 

 or two inches. The projecting points of the thorax, and the 

 sheath of the spine, served to steady the whole body during the 

 spring. In the descriptions which I have read, sufficient stress 

 does not appear to have been laid on the elasticity of the spine : 

 so sudden a spring could not be the result of simple muscular 

 contraction, without the aid of some mechanical contrivance. 



On several occasions I enjoyed some short but most pleasant 

 excurisions in the neighbouring country. One day I went to 

 the Botanic Garden, where many plants, well known for tiieir 

 erreat utility, mii2:ht be seen OTowing. The lea'-es of the cam- 

 phor, pepper, cinnamon, and clove trees were delightfully aro- 

 matic ; and the bread-fruit, the jaca, and the mango, vied with 

 each other in the magnificence of their foliage. Tlie landscape 

 in the neisihbourhood of Bahia almost takes its character from 

 the two latter trees. Before seeing' them, I had no idea that 

 any trees could cast so black a shade on the ground. Both of 

 them bear to the evergreen vegetation of these climates the same 

 kind of relation which laurels and hollies in Eno^land do to the 

 lighter green of the deciduous trees. It may be observed, that 

 the houses within the tropics are surrounded by the most beau- 

 tiful forms of vegetation, because many of them are at the same 



* Kirby's Eatomolop^y, vol. ii., p. 317. 



