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HA RD WICKE'S SCIENCE- G OSS IP. 



pistil grows upwards and comes to light, positively 

 dragging with them the pollen from the stamen tube, 

 and making it available for the various visitors to the 

 flower. Add to this, that the pistils do not open for 

 some little time after appearing, and we can see how 

 the chances of a cross are favoured. 



And what is the purpose of the angular pieces 

 referred to ? With some diffidence I venture the 

 opinion that it is for ventilation of the stamen tube, 

 which, owing to its size, could not be effected without 

 some mechanical aid, it being impossible to create a 

 current through so small a space without a special 

 contrivance. The method is this : an insect, in 

 seeking nectar, necessarily thrusts its proboscis 

 against an angular piece and presses it inwards, 

 thus causing a slight displacement of air in the tube, 

 and this, oft repeated, would be sufficient to carry out 

 the end in view. But it may be urged that I ought 

 first to prove that ventilation is necessary before 

 showing how it is effected. This, however, I cannot 

 do. I can only surmise that it would be advantageous 

 to the pollen to have a constant supply of fresh air to 

 keep it vigorous. The angular pieces, it is reasonable 

 to suppose, like any other part of the flower, whether 

 rudimentary or otherwise, subserve some useful 

 purpose ; but I am not in the position to advance 

 conclusive evidence for any specific purpose. It is 

 true that a part, in transition or otherwise, may be, 

 as far as we can ever learn, absolutely useless except 

 for enforcing a lesson in evolution ; but I do not 

 think we can look upon these angular pieces only in 

 this way, and I believe they are of actual service. 

 Take another instance, the rudimentary calyx : the 

 feathery pappus ultimately aids the seed, by means of 

 the wind, to find pastures new. When the seed 

 settles, as it not infrequently does, on grass, the 

 spines on the hairs and the spines on the achene, 

 pointing upward, act as resisters to the seed being 

 washed up above the surface of the earth when it 

 has once been washed down by the rain through the 

 grass. Otherwise the whole apparatus is so light that 

 it would hardly find its way through close grass to 

 the soil, and, when there, would stand less chance of 

 becoming fixed. With few exceptions, it is generally 

 found that any part, however useless it may at first 

 sight appear, is indispensable to the plant. 



224 Cambenvcll Neiv Road, London. 



LEPIDOPTERISTS' WORK FOR MAY. 

 By W. Finch, jun. 



WITH the " merry month of May," the lepidop- 

 terist's work begins to be almost more than 

 he can manage ; indeed he must needs be energetic if 

 he means to grapple successfully with the constantly 

 increasing insect life around him. 



Let him not merely satisfy himself by making a 

 collection and amassing specimens, but let him 



study, and study patiently, intently and well. He 

 will then at the end of the year be in the possession 

 of a collection of notes and a mass of information 

 such as will be both useful to further studies and 

 beneficial to heart and mind. Day by day new and 

 startling wonders will be unfolded to his gaze, and I 

 trust he will not allow them to slip unheeded by. 

 Here in these humble, tiny forms of life he will find 

 much for serious study and meditation ; for in the 

 tiniest and apparently most insignificant objects he 

 will find strong proof and forcible evidence of the 

 love, care, and wisdom of an omnipotent God. 



Let us see then what we have before us to get 

 through, and then to work with a will. What was 

 said last month concerning ova applies equally to 

 this. My readers should bear in mind that the 

 rearing of insects from the egg or from the early 

 larval stages is far more conducive to perfect 

 specimens and the acquisition of valuable knowledge 

 than any other method. Besides, there is much to 

 be discovered by this means and in this direction. 

 Many larvae there are of which we cannot be certain 

 as to their proper natural food-plant ; therefore every 

 student in this branch should make it his duty to take 

 copious notes of what he sees around him, jotting 

 down from time to time full particulars of food- 

 plants, habits, appearances, and any interesting or 

 striking characteristics that occur to him ; no matter 

 how trivial they may seem, put them down. 



With regard to larvae, much is to be done this 

 month. Beating may now be resorted to, for the 

 trees have by this acquired considerable foliage. 

 Hybernated larvae will be now about full fed, and 

 will be eagerly sought after, as giving comparatively 

 little trouble, soon turning into fine healthy pupoe. 

 Many small larvae produced from eggs laid late in 

 the spring will also be found, but should not be 

 despised, for they are as a rule free from those 

 parasites to which they are more liable later on. 

 Cannibal larvae must be carefully sought out and 

 isolated, or they will most assuredly devour their 

 brethren. The worst of them is C. trapezina, but 

 there are others, as P. cassinea, C. spartiata, S. satcl- 

 litia, which are quite as bad. Grass-feeding larvae are 

 now very plentiful. The lantern must still be used 

 for night searching. There are no reliable methods 

 of attracting larvae to us as we do moths, so we must 

 perforce go after them. Some collectors however 

 recommend lettuce-leaves as a bait, scattered about 

 on the ground some time before collecting. 



The essential points in successful larvae breeding 

 are quiet, plenty of room, fresh air and cleanliness. 

 Therefore let your cages be roomy and well-venti- 

 lated. [With our Editor's kind permission, I will 

 write a practical article before long on the " Con- 

 struction of Larvae Breeding Cages."] Never allow 

 your larvae to run short of food, and above all feed 

 from the same plants or trees throughout ; do not 

 change about from one tree to another : once you 



