July 10, 1884] 



NA TURE 



241 



to aid the self-fertilisation of the flowers the collecting-hairs on 

 the style of Campanulaceas and Composite (see Sprengel, 

 pp. log and 370), the pollen-masses of OrchideEe and Ascle- 

 piadeae being fixed near the stigma (Sprengel, pp. 401 and 

 139), the movements of the stamens of Parnassia, Ruta, and 

 Saxifraga (Sprengel, pp. 166, 236, and 242), as well as the 

 movements of the stigmas of Nigella, Passiflora, and Epilobiinn 

 (Sprengel, p. 280, 160, and 224). I do not know how to 

 reconcile these errors with Prof. Hagen's statement that Kunth 

 was "beyond doubt acquainted with the facts" discovered 

 by Sprengel. He "beyond doubt" never read Sprengel's 

 book, and I can explain those numerous and crass errors of one 

 of the most celebrated botanists only by the assumption that at 

 that time Sprengel had fallen into almost complete oblivion 

 among German botanists, and remained so till, as Prof. Mobius 

 justly remarks (Nature, vol. xxix. p. 406), "the value of his 

 treatise in its bearing on the theory of selection was first recog- 

 nised by Charles Darwin." Fritz Mullek 

 Blumenau, Santa Catharina, Brazil, May 25 



Voracity of the Drosera 



I AM not aware that the Drosera has been noticed to capture 

 so large an insect as the dragon-fly, Pyrrhosoma minium. Pass- 

 ing a pond-side on a bright June morning, where this insect was 

 flying plentifully, and near which Drosera rotundifolia was 

 growing in abundance, I saw that many of these insects had 

 fallen victims to the carnivorous propensities of the plant. On 

 one spot about a foot square I counted six plants which had 

 captured specimens of the dragon-fly, besides smaller insects. 

 One plant had possessed itself of two of the dragon-flies, one 

 being partially digested and the other freshly caught. The 

 Drosera plants, being young, were in many instances less in 

 expanse than the dragon-flies caught upon them, which measure 

 about two inches across the wings, with a body about one inch 

 and a half long. The dragon-flies appeared to be attracted to 

 the plants by the reflected sunlight glistening upon the beads of 

 fluid secreted from the leaves, and from which the plant receives 

 its common name of "sun-dew." Those dragon-flies which I 

 saw caught hovered over the plants about a second, at a distance 

 of three or four feet, and then darted upon the plant, when they 

 were instantly caught. A. Balding 



Wisbech, July 3 



Lightning 



At this time of the year one commonly reads of persons being 

 struck dead, blind, or serseless by lightning ; some of the phe- 

 nomena are very puzzling, especially in cases where persons are 

 but slightly injured. 



On June 6, 1881, I was in the open country near the sea 

 between Gosport and Southampton, in a place where there was 

 no shelter. Here I was suddenly overtaken by a violent storm 

 of thunder, lightning, and rain. Before I had time to think of 

 escape, the air became darkened by the pouring rain, and, to 

 save myself from a drenching, I perhaps foolishly put up my 

 umbrella ; at the same instant I saw a blaze of fire on the right- 

 hand side of my face ; the thunder burst at the same moment, 

 and a violent wrenching pain seized the fingers of my right hand 

 (which held the umbrella), the pain instantly travelling to my 

 elbow and shoulder, where it ceased. With the exception of a 

 strong pain in the arm like rheumatism for the rest of the day, I 

 felt no further ill effects. 



There is a blind beggar sometimes seen about here who carries 

 a label stating that his eyes were destroyed by lightning ; there 

 is no iris to either eye ; both are quite white. One day lately I 

 asked him how he lost his sight. He said that he was leaving a 

 country public-house during a thunder-storm, and he received 

 the blow from the lightning at the street-door, as he stood on 

 the top of a short flight of stone steps. He could only remem- 

 ber seeing the blaze of the lightning, and being hurled to the 

 ground down the steps into the street. On his senses returning, 

 he was blind. He states that he had a little glimmering sight 

 at the time of recovery, but first one eye and then the other soon 

 became totally blind. 



A few years ago several letters appeared in Nature regard- 

 ing the descent of balls of fire in thunder-storms. On July 5, 

 1881, whilst watching a storm from my windows at 11.30 p.m. 

 I distinctly saw in the south a ball of fire drop from the clouds 

 to the earth. The descent was rapid, but not comparable with 



lightning, and with an inclination to the east. The ball appeared 

 large, and about one-half or one-third the apparent size of the 

 moon. A carpenter who was working for me at the time, Mr. 

 George Hebb, on calling upon me a few days after the storm, 

 told me (I had not previously mentioned the matter to him) that 

 he had seen the descent of the same ball of fire from Mildmay 

 Park whilst he was walking towards the south. It is the only 

 example I have seen. Worthington G. Smith 



Solar Halo 



On Friday, June 27, about 5 p.m. my attention was drawn to 

 a solar halo which lasted for about two hours from that time ; 

 the circular part of the halo was white, and about the size of an 

 ice halo, the sun apparently about four times its proper size and 

 of badly-defined outline ; all within the halo was darker than 

 the rest of the sky, and vertically over the sun there was about 

 an octant of another circle (?) touching the first one, but prismaii- 

 cally though not brilliantly coloured. On Saturday night there 

 was a strong pink glow from 9 to 9.30 in the north-north-west, 

 with a greener sky near the moor, which was itself also some- 

 what green. W. W. Taylor 



INSECT PESTS IN THE UNITED STATES 1 



THIS volume is issued under the auspices of the De- 

 partment of Agriculture, and relates entirely to five 

 insect pests. The book is full of matter of general as 

 well as of purely scientific interest, and abounds in sugges- 

 tions for checking and exterminating the pests of which 

 it treats. 



One rises from its perusal with a sense of thankfulness 

 for our temperate climate, insularity, and moderate dimen- 

 sions. These conditions are unfavourable to excessive 

 multiplication of insect life ; and hence we escape the 

 locust, the canker-worm, and the palmer- worm, 111 their 

 full devastating energy. The connection between solar 

 activity and swarms of insects forms a special section ; 

 and the relation between sunspots and locust flights is 

 drawn out in tabular form, showing a striking coincidence 

 between special locust visitations and the minimum of sun- 

 spots. This is of course merely a scientific way of show- 

 ing that hot summers breed insects. The Report deals 

 with the Rocky Mountain Locust, the Western Cricket, 

 the Army- Worm, Canker- Worm, and Hessian Fly, and 

 the treatment of the subject is a full justification of the 

 existence of such a Commission. 



An Entomological Section of an Agricultural Department 

 appears to be an absolute necessity in those vast regions, 

 and the facts and phenomena are so startling as to be 

 worthy of constant watchfulness, and this can only be 

 secured by a special and permanent Commission. On 

 the other hand, the powerlessness of man in dealing with 

 the actual invading forces of the winged or creeping 

 armies of Hexapoda is constantly exemplified. It is truly 

 observed that the only effective method of dealing with 

 insects is to study their habits, their structure, their weak- 

 nesses, their devolution. It is here that the entomologist 

 shakes hands with the agriculturist. The cultivator is 

 paralysed by the magnitude of the devastation, and the 

 best he can do is to take such self-evident means as are 

 at once available, such as burning, rolling, roping, or the 

 like. The entomologist works less precipitately, but more 

 surely, in studying the sexual and maternal habits of the 

 imago, the conditions favourable to incubation, the hatch- 

 ing and development of the larva, the transformations to 

 the pupal and perfect forms, and lastly, the food and 

 habits of the mature insect. 



All the; and other matters are searched into by the 

 State entomologist much upon the same principle as a 

 Government section collects information as to the habits 

 and resources of some nation with which it may at some 

 time find itself at war. Thus the Entomological Commission 



' "Third Report of the United States Entomological Commission. 

 (Washington Government Printing Office, 1883.) 



