1832.] PHOSPHORESCENT INSECTS. 21 



The house in which I lived was seated close beneath the well-known 

 mountain of the Corcovado. It has been remarked, with much truth, 

 that abruptly conical hills are characteristic of the formation which 

 Humboldt designates as gneiss-granite. Nothing can be more striking 

 than the effect of these huge rounded masses of naked rock rising out 

 of the most luxuriant vegetation. 



I was often interested by watching the clouds, which, rolling in 

 from seaward, formed a bank just beneath the highest point of the 

 Corcovado. This mountain, like most others, when thus partly veiled, 

 appeared to rise to a far prouder elevation than its real height of 

 2,300 feet. Mr. Daniell has observed, in his meteorological essays, 

 that a cloud sometimes appears fixed on a mountain summit, while 

 the wind continues to blow over it. The same phenomenon here 

 presented a slightly different appearance. In this case the cloud was 

 clearly seen to curl over, and rapidly pass by the summit, and yet 

 was neither diminished nor increased in size. The sun was setting, 

 and a gentle southerly breeze, striking against the southern side of 

 the rock, mingled its current with the colder air above, and the vapour 

 was thus condensed ; but as the light wreaths of cloud passed over 

 the ridge, and came within the influence of the warmer atmosphere of 

 the northern sloping bank, they were immediately redissolved. 



The climate, during the months of May and June, or the beginning 

 of winter, was delightful. The mean temperature, from observations 

 taken at nine o'clock, both morning and evening, was only 72'. It 

 often rained heavily, but the drying southerly winds soon again 

 rendered the walks pleasant. One morning, in the course of six hours, 

 1-6 inches of rain fell. As this storm passed over the forests which 

 surround the Corcovado, the sound produced by the drops pattering 

 on the countless multitude of leaves was very remarkable ; it could be 

 heard at the distance of a quarter of a mile, and was like the rushing 

 of a great body of water. After the hotter days, it was delicious to 

 sit quietly in the garden and watch the evening pass into night. 

 Nature, in these climes, chooses her vocalists from more humble per- 

 formers than in Europe. A small frog, of the genus Hyla, sits on a blade 

 of grass about an inch above the surface of the water, and sends forth a 

 pleasing chirp : when several are together they sing in harmony on 

 different notes. I had some difficulty in catching a specimen of this 

 frog. The genus Hyla has its toes terminated by small suckers ; and 

 I found this animal could crawl up a pane of glass, when placed 

 absolutely perpendicular. Various cicadae and crickets, at the same 

 time, keep up a ceaseless shrill cry, but which, softened by the 

 distance, is not unpleasant. Every evening after dark this great 

 concert commenced; and often have I sat listening to it, until my 

 attention has been drawn away by some curious passing insect. 



At these times the fireflies are seen flitting ;about from hedge to 

 hedge. On a dark night the light can be seen at about two hundred 

 paces distant. It is remarkable that in all the different kinds of 

 glowworms, shining elaters, and various marine animals (such as the 

 Crustacea, medusae, nereidae, a coralline of the genus Clytia, and 



