Vol. XVI. No. 397. 



THE AGRICULTURAL NEWS 



219 



cell, which it has previously formed from part of its tunnel. 

 It then changes into the pupa and later to the adult. It 

 was found that while the grubs were in the active larval 

 stages they were often able to resist diseases or attacks by 

 mites, but during the quiescent prepupal and pupal stages 

 they succumbed, either to injury, or to the attacks of mites 

 or of the bacterial disease. Micrococcus nigrofaciens. Many 

 hundreds of eggs were hatched out, but the grubs obtained 

 from them gradually died off in the different stages before 

 issuing as adults, with the result that only about twenty 

 beetles of P. vandinei eventually emerged. 



Check experinients for each species were carried on in 

 large outdoor rearing cages with earth in which cane or corn 

 was grown as food. A number of adults were liberated in 

 them, one species in each cage, about the same time that the 

 indoor experiments were started. The adults were removed 

 about a week later, eggs having been deposited meanwhile in 

 the soil. The cages were left undisturbed, except for 

 occa.sional attention as to food and moisture, until the grubs 

 passed through their various stages and the adult beetles 

 emerged. It was found that the adults from grubs in these 

 outdoor cages emerged at the same time as the adults from 

 grubs in the tin boxes, provided that a grub escaped the 

 attacks of mites, fungus or bacterial disease. In the case of 

 the species Phytalus insularis, no larvae reared in tin boxes 

 reached maturity, so that the length of the life-cycle had to 

 be determined from the results obtained in the outdoor 

 cages. 



In the next issue details will be given about the life- 

 cycle of Phyllopha/ja vandinei, and mention will be made of 

 the natural enemies of white grubs in Porto Rico 



J.C.H. 



BEES IN RELATION TO AGRICULTURE. 



In a icpoiL ^iviug an ascount of a recent visit to the 

 coco-nut districts of the colony, the Government Entoniolo 

 gist of Fiji noticed that, on those estates where bees were 

 kept, the bees swarmed around the open efflorescences in 

 great number.^, and that the yield on those estates was 

 exceptionally high. As trees of five or six years bore heavy 

 crops and the bunches were well filled it is recommended 

 in the report that a general introduction of bees on coco-nut 

 estates would be well worth a trial. Similar observations 

 have been made in regard to lime plantations. 



Sufficient importance is not paid to the part played by 

 insects in the fertilization of plants, and the usefulness of the 

 bee is but scantily recognized by planters in the West Indies. 

 The bee is one of Nature's silent workers, and this, perhaps, is 

 the reason why the benefits derived from their work is not 

 appreciated at their full value. Some years ago, a bee 

 expert, at the instance of the Imperial Department of 

 Agriculture, visited several of the West Indian islands to 

 stimulate interest in bee-keeping, but, although some 

 persons were induced to establish hives for the production 

 of honey and wax, the fact that the bee's most important 

 work is that of the fertilization of plants was practically 

 overlooked, and it nny therefore be of practical benefit to 

 discuss briefly the process of that work. 



The object of plants blossoming is, as is well known, to 

 produce perfect seed and to perpetuate the race. More 

 than 200 years ago, it was discovered that, to produce 

 seed, pollen must be placed on the stigma, the female 

 part of the plant. Although most flowers possess both 

 anthers, the male part, and stigmas, and have thus the two 

 sexes within themselves, which would lead us, to suppose that 



such a form of flower would insure the transmission of the 

 pollen to the stigma so that the object of its blossoming might 

 be accomplished, it has been found that the protest made by 

 Nature against inbreeding applies no less to plants than to 

 animals. It is now established that the structure of conspicu- 

 ous flowers, generally speaking, is such as to prevent, or at 

 least to impede, fertilization by their own pollen, for it has 

 been discovered that the male flowers and female flowers on 

 the same spadix do not mature at the same time. As pointed 

 out in a recent number of the Journal of ihe Jamaica 

 Agricultural Society, the males open soon after the spathe 

 or covering bursts, and the pistillate at a later period. As 

 a rule, too, one set of flowers opens or is ready to feitilize or 

 to be fertilized at a period not coincident with the opening 

 of the other set. This is one of Nature's devices calculated 

 to guard against inbreeding or self-fertilization, and insures 

 that fertilization from another coco-nut must take place. 



The question naturally arises how the fertilizing dust 

 is carried from one flower to another, but Nature, in this 

 matter also, has provided curious arrangements to secure to 

 a plant the pollen from some other plant or flower of the 

 sime species. For some plants the work is done by the 

 wind wafting pollen from one plant to be caught by another 

 on the branched and hairy .stigmas which grasp it as it 

 travels past. But, just as one of the most striking advances 

 in our knowledge of the mode of causation of disease is our 

 recognition of the important part taken by many insects 

 in giving rise to various maladies, we have also been taught 

 by the carefully conducted observations of Darwin and other 

 naturalists, that the fertilization of many plants can only be 

 accomplished if certain definite insects are present which 

 can carry the pollen from one plant to another, and that if 

 an attempt is made to grow those plants in a district where 

 those special insects are not to be found, the plants, 

 though they may grow in great luxuriance, can never set 

 their seeds. An instance of thi.': is to be seen in the case 

 of the vanilla plant. Amongst insects, bees are of the 

 greate.st utility in fertilization. As the visits of these insects 

 are necessary to the existence of the plants, the flowers, by 

 their attractive dress and sweet perfume secure these visits. 

 The blossoms themselves, it is true, require pollen, but the 

 quantity produced is much greater than what is required 

 for blossom fertilization. The excess is the food of the bee, 

 while nectar from which honey is derived is principally 

 produced as a reward for its services. In this way, insects 

 and flowers are mutually dependent on each other for 

 existence. 



A colony at full strength consists of three kinds of bees: 

 one queen at mother, forty to fifty thousand workers, and 

 several hundred drones. The queen is the mother of every 

 bee in the hive and doe^ no work but that of reproduction, 

 while the drones are the males, tlieir only use being the 

 perpetuation of the species. The worker is the only 

 one to collect honey, her tongue, which is long to enable 

 her to reach to the bottom of the flower, being provided at 

 the tip with a brush for the collection of tiny particles of 

 pollen. The body, especially the underside, is covered with 

 feathery hairs, to which the pollen grains adhere and which 

 thus become the medium for conveying pollen from one plant 

 to another. The hind-legs have also a pollen basket in 

 which the surplus pollen is carried to the hive, where it is 

 stored and eventually used for food. 



Apart from apiculture being a fascinating study, the 

 keeping of bees may be of direct advantage in the production 

 of honey and wax, and of less apparent, but equal, profit in 

 increasing the yield of fruit and other crops by the aid given 

 to fertilization. 



