764 Retrospective Criticism, 



menon be solved by attributing it to the presence of the male 

 glowworm ? A friend of mine some years ago related to me 

 the astonishment he once felt, in riding across a moor in 

 Somersetshire, in seeing a light flitting about his horse's bridle, 

 and advancing as he advanced for a considerable distance. 

 About a month ago, one of my domestics observed a soft and 

 beautiful light (flame as he conceived) flitting in a field ad- 

 joining my residence. I have no doubt it proceeded from a 

 male glowworm, and I have this year traced the jLampyris 

 noctiluca, both male and female, through all its stages. In 

 the larva state, both male and female emit their light from 

 two points near the extremity of the end of the body ; in the 

 nymph state the light is also, although more feebly, displayed. 

 On emerging to its perfect state, the female emitted light from 

 eleven points, but most brilliantly from two, and the male from 

 two only. Within the last six weeks there has scarcely been 

 an evening when my study windows have been open, in which 

 a male glowworm (and sometimes three or four in the course 

 of the evening) has not flown in ; all of them exhibiting their 

 light, either voluntarily or on being excited by meddling with 

 them. I had two or three female glowworms on a turf under a 

 receiver in one corner of the room, and it is not improbable 

 that sexual instinct was the occasion of my being so nume- 

 rously visited. The male glowworm I have observed to live 

 from two to four days after introduction to the female ; and 

 the latter to survive ten days or a fortnight, having laid a vast 

 number of eggs. — Albert, July 12. 1832. 



Of Winds, (Vol. II. p. 175.) — • Mr. Main, speaking of the 

 trade winds blowing constantly from east to west, says : — 

 " This is caused by the cooler air of evening pressing west- 

 ward upon the heated air of midday ; in other words, the 

 lower temperature of the air in the place to the eastward of 

 the sun causes it to press westward upon the rarefied air of 

 the place over which he is vertical." It may be sufiicient here 

 to observe, that, if this were granted, it might produce an 

 easterly wind in the evening ; but it would also produce one 

 from the west in the morning. In fact, however, the tempera- 

 ture of the surface of the sea, in the places Mr. Main mentions, 

 is not sufficiently affected by the midday sun to produce any 

 such consequences : it is, indeed, scarcely perceptibly raised. 

 The generally received and probably correct explanation is, 

 that the currents of cold air from the poles, spoken of by Mr. 

 Main in his concluding paragraph, reach the equatorial 

 regions without having entirely acquired the equatorial whirl- 

 ing motion. — A Subscriber, Vale of Alford, Sept, 28. 1832. 



