Insect Pests OF THE Lesser Rntilies Bv H. ^. B^hhOlJ, M.& Eatcrmologist on the Staff of the Impmai Department of Hgrledtui^ I8$u6cl by Ihe Sommissiofiif of ftgrisnltoc mt LIBRARY OF 1885- IQ56 Pamphlet Series, No. 71. IMPERIAL DEPARTMENT OF AfiRIOOLTDRE FOR THE WEST INDIES. mSECT PESTS OF THE LESSER ANTILLES. By H. a. BALLOU, M.Sc, Entomologist on the Staff of the Department. ISSUED BY THE COMMISSIONER OF AGRICULTURE. 1912. Printed bj' Advocate Co., Lti>., Biidgetowu, Barbados. (Ill) PREFACE. This Handbook, (lealin<]f with the Insect Pests of the Lessei- Antilles, has been prepared by Mr. H. A. Ballon, M.Sc , Entomologist on the Htatf of tlie Imperial Department of Ac^ricuUnre, with the object, as is stated by the Anthor, of giving in plain and simple langnage, 'a brief general account of our present knowledge of some of the principal insect and mite pests of the crops grown in the Lesser Antilles ; also of the pests attacking man and domestic animals, as well as of those of the household.' As is stated further, the scope of the work does not admit of the presen- tation of detailed accounts of insects, nor of descriptions of .ill insect enemies of plants in the West Indies. An attempt at such a presentation would actually have defeated its object, as this is outlined above ; whereas on the contrary, a P'-rusal of the work as it stands is sufficient to show that this object has been fully and usefully attained. The arrangement of the subject-matter is such as to make reference easy, and to bring forward the information in such a way that each subject falls into its natural place ill the sequence. The large extent to which illustrations have lieen employed will add greatly to the usefulness of the work, particularly in so far as it is employed by practical agriculturists. Its educational character will doubtless be found of value in connexion with nature teaching and lessons in agi'icultnre in Schools ; in the hands of the teacher it will assist in presenting and formulating the information to be given, and will aid in providing and identifying tlie specimens that are required indispen.sably for demonstration. The Handbook presents, to a great extent, a carefully prepared summaiy of information contained in a large pumb^r of entomolDgical publications of different kinds, and (IV) this fact is sufficient in itself to make it particularly useful to agriculturists, as well as to others by whom it will doubtless be consulted, who do not possess the time or the facilities for reference to entomological subjects that are of importance to them. My thanks are due to Mr. Ballon, for the careful way in which the work has been compiled, and it is due to him, also, to place the fact on record that the book derives an additional value, which will be recog- nized to an increasing extent as it comes into general use, from the circumstance that it presents information that is the outcome of his special work and observation in the West Indies— information that in many cases relates to forms of insect life, both injurious and beneficial, that were not known previously to be of economic importance. / Commissioner of Agriculture for the West Indies. (V) Entomologist, To the Imperuil Commi-sfiioner of Agriculture. Sir, I have the lionour to submit, herewith, a manuscript with ilhistratioiis, which I have prepai'ed for pul)licatioii as a Handbook of Insect Pests of the Lesser Antilles. This might be included in the Pamphlet Series of the publica- tioi^s of this Department. 2. The oliject of this book is to present, in plain and simple language, a })rief genej-al account of our present knowledge of some of the principal insect and mite pests of the crops grown in the Lesser Antilles ; also of the pests attacking man and domestic animals, as well as of those of the household, ?>. It would not V)e possible, within the scope of a small work, to include an account of all the insects which are known to attack plants in the West Indies, nor to give detailed accounts even of the more important ones without greatly exceeding the limits of such a volume as this. 4. I can make no claim for originality in connexion with the information presented herewith, although much of what is here given has already appeared in articles prepared by me for publication in the Agricultural NewK, the West Indian Bulletin and the Pamphlet Series ; and in so far as these articles have referred to work done by me under the direction of the Imperial Commissioner of Agriculture, they were records of original work. This last is especially true of certain pests which have appeared in these islands during the past nine years, as new pests unknown in other localities. 5. The recorded knowledge of many of the forms of insect life which are of common occurrence in many parts of the world, is distributed throughout entomological publi- cations, such as text-books and the publications of Depart- ments of Agriculture and of Experiment Stations. A considerable amount of such general knowledge has, of course, been utilized in the preparation of this work, a ceitain amount of it having been verified by observation and experiment. 6. Since this book is entirely jjopnlai' and the informa- tion has appeared previotisly in the publications already mentioned. 1 have made no attempt to cjiiote references to authorities. 7. Planters and others who use this hook are almost certain to find many points where the information giren fails to apply exactly to the local conditions. If these differences could be reported and recorded, the added information thereby acquired would be extremely useful in preparing a revision, if that should become desirable. 8. The blocks from which the illustrations are produced are all in the possession of this Department, having been acquired during the past twelve yeais from several sources, which are indicated on another page, where acknowledg- ments are made. The source from which the blocks have been obtained is stated alsa in connexion with the legend which is given with each tign'-e. 9. The Rev. N.B. Watson, F.E.S., has been kind enough to read the proof critically : for this I desire to express my thanks. I have the honoiu- to be, Sii-. Your most obedient servant, (&gd.) H. A. BALLOU, Entomologist. (VII) ILLUSTRATIONS. Tlie illustrations which ;ij)pear in the ful]owiii9, 1(10, 101, !(>:>, KM, 105, 115, 131, 132,133,135 i: (j 137. 139, 1 10, 111. 1 12. 1 13. Ill, 1 15, 1 IH. 1 17. 1 18, 119, 15o' 151, 152. 153, 154, 157, 158, 159, KiO, ItJl, H)2. 1(13. 1H4. Iti5 Kit), l(i7, 1H8, 17H, 177, 183, and 184. Figures 45 and 47 are from blocks procured througli the courtesy of the Secretary of the New York Entomo- logical Society. The blocks for figures 170, 171, 172, 173 and 175 have been presented to this Department by the manufacturers of ajjparatus. The figures 11, 12. 14 and 174 have l)een ledrawn, fiom various sources which lia\e been ackno\\ledged in the legend in each case. Figures 49. 22, 21, 40, 41, 52. (30. (51. ()3. (11. tiH, ()7. H8. 69, 73, 74, 75, 78, 79, 82. 83, 85, 8H, 90. !<5. 9(), 97. lOH 107 109, 110, 111, 113, 114. 11(5. 117, 118, 119, 120, 12(i, 127, 128, 130, 138, 156, 179, 180, 181 and 182 are from drawings made by officers of the Department or under their direction. The half-tone block for figure 185 was prepared from a photograph forwarded by the Superintendent of Agri- culture, Grenada. All other half-tone blocks are from pliotogra])hs taken by the writer. These are all acknowledged as 'original ' in the legends, even though some of them have prevTously appeared in the publications of this Department. Those which have already been published are shown at figures 25 42, 43, 44, 65, 70, 91, 108, 121, 122, 123, 124, 425 and 169. ' The half-tone blocks which now appear for the first time are shown at figures 2, 3, 6, 7, 15, 20, 23, 26, 27, 3'^ 33 38 46, 55, 56, 71, 72, 80, 84, 89, 98, 112, 129, 134, 155, and 178. ' (.K) CONTENTS. I. Introduction. II. Insects and thkir Near Relations. III. Natural History of Insects. lY. Orders of Insects. V^. Insect Pests of Crops. VI. Insects which Attack Man. VII. Insect Pests of Domestic Animals. VIII. Insects of the Household and Pests OF Stored Products. IX. The Control of Insects. X. Insects and their Natural Enemies. CHAPTER I. Introduction. Tn 1901, the Imperial Department of Agriculture issued Pamphlet No. 5, entitled General Treatment of Insect Pests. At that time, the Department had recently begun to deal with the problems presented through the ^attacks of insects on crops, and consequently the information then i^ublished was of the most general character. The ten years which have since elapsed have brought about a much wider knowl- edge of the insects which occur in these islands. It may be well to remind readers of this book that the Imperial Department of Agriculture has-been in direct rela- tionship witli the agriculture of the British islands of the Leewaixl and Windward Colonies, and Barbados, and that references to the Lesser Antilles will be understood to apply to these Colonies onh*. The crops grown in the West Indies are much the same as they were ten years ago, the principal difference being in the standing of the cotton industry, which was then enter- ing upon an experimental trial. It need not be stated^ here what measure of success attended these trials, nor the rapidity with which a profitable industry was established. As a result of the rapid increase in the acreage of cotton, insects which previously were not recognized as pests, and in some cases even were not known to science, have assumed an important position as serious pests. Further study of the conditions in regard to the culti- vation of other crops has also led to the recognition, as pests, of insects which formerly were entirely ignored. In the following pages an attempt is made to present a general account, in popular language, of insects and their allies (mites and ticks) which are of importance. These are ari'anged in groups according to the plants or animals which they attack, and in many instances information is given as to their natural enemies. In addition to the remedies and control measures which ai"e suggested in connexion with the account of each pest the chapter on the control of insects gives information in regard to many insecticide substances with directions for making various mixtures. The use of insecticides is explained, and descriptions are given of the machinery and appliances adapted to their application. The insects which attack growing crops may be grouped in three main divisions, according to their manner of feeding, or their habit of living. These are leaf-eating, sucking, and boring. Leaf-eating insects are represented by a great variety of caterpillars, beetles and grasshoppers, which with their powerful mouth parts are able to bite off particles of the plant, which they chew and swallow. Sucking insects are those Avhich have their mouth parts developed in such a manner that they are able to puncture the tissues and suck out the juices of the plant. They are represented by scale insects, plant lice, white fly. cotton stainers, and bugs of several kinds. Under this heading, also, might be included thrips, red spider, leaf-blister mite, red maggot and flower- bud maggot. The hrst two of these, thrips and red spider, are intermediate in their feeding habits between the biting and sucking types of insect, their mouth parts being adapt- e I to enable them to gnaw away the sui-face of the tissue where they feed ; after this they obtain their food, probably by a process of lapping, from the freshly exposed tissues. The leaf-blister mite probably feeds in much the same wa}-, concealed among the plant hairs within the blister or gall which is produced on the plant by the ir_'itation due to its activities. The flower-bud maggot and red maggot live in nutritive tissue, and may absorb a certain amount through the skin. Boring insects are those which tunnel out for themselves galleries within the tissues of plants. Their attacks are made on the stem, the root, and the fruit of various plants. The boring is generally done by such insects when they are in the larval stage. Examples of this group of insects are to be found in the moth borer and weevil borer of the sugar- cane, the lime tree bark borer, the cacao borer, the palm weevil and others which bore into the stems of plants ; the root borer of sugar-cane, the scarabee of sweet potatoes and others which bore into the roots. Tlie minute larvae of certain flies and moths live as miners in the leaves of plants, forming galleries just beneath the epidermis. The mole cricket might also be mentioned in this connexion, on account of its underground hahit of Hfe and its manner of attacking the roots of plants, altliough it does not actually bore into tlie tissues, after the tvpieal manner of borers. Insects which bore into the fruit are represented by the cotton boll worm, corn ear worm and the larvae or maggots of fruit flies. Insects which are injurious to stored products are the meal worms, grain weevils and the cigarette beetle. Among those which are known as household pests may be mentioned cockroaches, crickets, ants, bed-bugs, clothes moths, cigarette beetles, silver-fish and house-flies. The insects which attack and injure domestic animals and man have come, within the last few years, to be recog- nized as of great importance, many of them being known to disseminate some of the most serious of diseases, and others being suspected as having a possible influence in the same direction. Among these may be mentioned fleas, flies, ticks, lice, the mites which cause itch, mange and scab, the screw worm, mosquitoes, chigoes or jiggers, bete-rouge and the bed-bug. In order that readers of this booklet may be better able to understand tlie insects with whicli they may have to deal, a short account follows of the group of animals which includes insects and their nearest relations, and of the natural history of insects. A brief account of the orders of insects gives the characters of each Order in such manner that, in general, there should be no difficulty in placing the greater number of insects in their correct Order ; and to aid further in this, a key is included, with directions for its use. CHAPTER 11. Insects and their Near Relations. The animal kingdom is divided into several great groups, or sub-kingdoms, in each of which the members have some points in common. One of these groups has 1>een given the name Arthro- poda, which means ' jointed feet', or perhaps, better, ' jointed limbs.' The arthropods a)-e all alike in having jointed limbs, and bodies that are jointed, or at least that are easily separable into regions or sections, such as head, thorax (the middle body) and abdomen ; or h.ead and hind body ; or cephalothorax (head and thorax fused together), and abdo- men. Arthropods have an exoskeleton of a hard, firm substance, called chitin, to which nuisoles are attached on the inside ; this protects all the soft and delicate organs The arthropods in their turn are divided into four classes as follows : — Class I. Crustacea— Crabs, Lobsters, Wood-lice etc. ,, II. Arachnida— Spiders, Mites, Scorpions, etc. ,, III. Myriapoda— Centipedes, Millepedes, etc. ,, IV. Hexapoda— Insects. Among the Crustacea are to be included crabs, lobsters, shrimps, barnacles, etc., many of which are familiar objects in most parts of the West Indies. Fig. 1 represents a wood-louse, or sow- bug, one of the crustaceans. The crustaceans are mostl}^ aquatic ; a few live in damp situations such as damp soil or decaying vegetable matter. They breathe by means of gills, the head is provided with two pairs of antennae, the abdomen has appendages which are used in locomotion and the eyes ai^e usually compound, sometimes stalked. The body generally is divided into two regions, the cephalothorax and the abdomen. The cephalothorax is composed of the head and the thorax fused together, and is often protected by a hard shell, the carapace. The exoskeleton of cliitin quantities of lime. is often impregnated with large The Class Araclmida includes the spiders, mites, ticks and scor- pion;:;. These animals breathe by means of air-tubes (tracheae), or air-sacs. Certain species, mite?, especially, liave the entire surface of the body adapted for respira- tion. In the case of most mem- bers of this group, the head and thorax are fused to forai a cepha- lothorax, and the eyes are simple. The scorpions (Fig. 2) are weU known in tropical countries, on Fig. I. Crustacean. account of the painful sting they A Wcod-louse. are able to inflict. The}^ are Enlarged. (From U. S. mostly predaceous and nocturnal Dej^t. Aiiric.) in hal)it, living in damp situations. Fig. 2. Arachnid. A scorpion. Slightly reduced. {Original.) The whip scorpions (Fig. 3) receive their uamefrom tlie long lash-like development of the first pair of legs. In the illustration these are the slender appendages which are t Fig. 3. Arachnid. A tailless whip scorpion. About natural size. {Original.) shown turned to the rear on the back of the animal. They are not known to be injurious or destructive. The s2Diders inchide many species of varying size and form. The four pairs of long legs fui-nish the most promi- nent character of this group. Fig. 4. Arachnid. The cattle tick. Female cattle tick at the left, tnalc at the right. Enlarged. {From U. S. Dept. Agric.) The ticks are parasitic on many forms of animals. The common cattle tick (Fig. 1) occurs on domestic cattle, ^while similar forms attack dogs, goats and fowls. They often transmit diseases, and on this account, in addition to being parasites they are the cause of serious loss. The red spider (Fig. 5) is a good example of the mites which attack plants, feeding on leaves, frints and bulbs. The Myriapoda, Class III, include the centipedes and the millipedes (Figs, b and 7.) These are elongate animals with segmented bodies and jointed limbs and appendages. niachnid. A red spider. (a)advlt ; [h) ]ial}im ; (c) claw. Enlarged. {From U. S. Depi. A(jvif.) thorax and the abdomen do not differ in structure, body is generally provided with legs throughout length, one or two pairs to each segment. The Centipedes (Fig. 6) are predaceous in habit. They are also venomous, and by means of the strong fangs formed by The head is distinct from the rest of the body, but the The hind its entire Fig. 6. Myriapod. A Centipede. Beduced. (Or iginal.) the modified first pair of legs are able to inflict painful and sometimes dangerous wounds. Fig. 7. Myriapod. Millipede. Reduced. (Oriyinal.) Fig. 8. A primitive insect. The silver-fish. Adult. Enkuyed. {From U. S. Dept. Atjric.) The Millipedes (Fig. 7) are most!}' scavengers, feeding on decaying vegetable matter, though sometimes they attack growing plants. They are not often pests, however. Class IV is the Hexapoda, or true insects. The name Hexa- poda means having six legs, and this expresses one of the most distinguishing characters of the insect. In addition to be- ing arthropods having six legs, insects are to be distinguished from others of the group by the followi]ig features. The insect body is readily separa])le into three definite regions— head, thorax and abdomen, and the adult is usually winged. The normal number of wings is two j^airs, but it sometimes hap- pens that one, or even both, pairs of wings is wanting, as in the silver-fish (Fig. 8). CHAPTER III. Natural History of Insects. Structure and Growth. As has l)een stated already, insects are animals which, in the adnlt condition, have never more than six legs, and generally, two pairs of wings (\vhich may be wanting but are never more in number), and a body made up of three Fig. 9. Insect with incomplete metamorphosis. A cockroach. (<(^{b) ((•) (), reprodi^ciive organs. {Redrawn from Coms'ock's Manual for the Study of Insects.) higher animals ; it tills the body-cavity and bathes all the organs, even penetrating into the legs and winga. It is usually colourless, but is sometimes tinted yellowish, green, and even red, but does not derive its red colour from red corpuscles, and is not red blood in the same way as is the blood of the higher animals. 14 The organ of circulation is the heart or dorsal vessel. As has been said, it is called the dorsal vessel because of its position in the body, lying as it does along the median line of the back, just inider the body wall. The heart is a straight, unbranched, tubular organ provided with muscles, extending from the hinder end of the bod}' to the head ; it is generally closed at the posterior end and open anteriorly. The portion lying within the abdomen is constrictejd at intervals, and at each constriction there is a valve. These valves divide the dorsal vessel into compartments or chambers. By means of a rhythmic contraction and expan- sion of the walls of the dorsal vessel, accompanied by a regular opening and closing of the valves, the blood is forced from the rear toward the head, to the long aorta-like portion of the dorsal vessel lying within the thorax. The chambers are provided with small openings which communi- cate directly with the body-cavity, and througli which the blood in the bodv-cavity is taken into the heart and put into circulation. The pulsations of the dorsal vessel and the movement of the blood in the body-cavity can easily be observed in certain caterpillars. The arrowroot worm, or canna leaf- roller (Calpode^ ethliw<), is the best of our common West Indian insects for the purpose. Respiratiox. Insects breathe by means of air-tubes (tracheae) which begin at openings in the body wall, and extend througliout all parts of the insect structure. The apertures, which are called spiracles, or stigmata, are valvular, and are capable of being opened and closed. On the outside, they ai-e also generally protected by hairs. There are usually ten stigmata on each side of the insect body ; but there are sometimes less, and they also vary in their position, according to the life- habits of the insect. They may be distinctly seen with the naked eye in many insects. In certain large caterpillars, they are surrounded by fine lines, or are enclosed in spots of colour, which make them prominent. In the grasshopper, they may be easily seen — two on the sides of the thorax, and eight on the abdomen. The tracheae are composed of chitin, and are continuous with the body wall. The smaller air- tubes are simple tubular structures, but the larger are strengthened on the inside by ridges, arranged siDirally. 15 The tracheae from the stig- mata connect with main lines, wliich extend the length of tlie body ; from these the branches and smaller tubes com- nnuiicate with all parts. In Fig. 12, the cross-shaded por- tions are the ti^acheae. the ver}' line cross lines representing the thickenings mentioned above. In large insects which fly long distances, snch as pond-flies, butterflies and moths, some beet- les, flies, bees, etc., there often occur large distensions of cer- tain tracl:eae to form air sacs, which are probably of use to the insect in making the body more buoyant, and in increas- ing the rapidity of breathing. Insects are air-breathers, with few exceptions; most cf those which live in the water must come to the surface from time to time for a supply of air, and in many cases the habit of living in water, in decaying or- ganic matter, in plant tissues, or as animal parasites, necessitates some modification, or special adaptation, in the manner of obtaining the necessary air. Mo-squito larvae (Fig. 13) breatlie by means of a special organ at the posterior end of the body, which is brought into contact with the air. Maggots^of flies which live in plant or animal tissues often have spiracles at that end of the body, which ciommunicate with the air. In the accompanying illustration (Fig. 1.3) the tracheal tube, at the posterior end of the body, is shown at right angles to the body. The main tracheal trunks are indicated b}' the faint lines which may be traced through the segmented abdomen into the broad thorax, where they diverge. Water beetles come to the surface and carry down, when they dive again, a film of air held by the fine hairs of Fig. 12. Tracheal system of cockroach. {Redrawn after Miall & Denny.) 16 the bodv, while certain insects are provided with tracheal gills, in "the aquatic larval stage. In the case of the larva of the pond-fly and of a few other species, the modifications of the tracheal system adapt the insect to a completely aquatic existence over a certain portion of its life-cycle. In these instances, which are the exceptions rather than the rule, the insect derives oxygen from the water in a manner exactly similar to that employed by fishes, which breathe by gills. W Fig. 13. Larva of mosquito. (Fiom U. S Dept Auric) The aeration of the blood is accomplished in a manner exactly opposite to that in liigher animals. The air penetrates to all parts of the body by means of the tracheae, which are bathed by the l^lood, and comes into intimate contact with the food-substance by means of the minute branches of the tracheae which envelop the alimentary canal. Nervous System. The relative positions of the ^■ital systems are also opposite in insects to those in higher animals. In insects the circulatory system is dorsal, and the nervous system is Fig-. 14. Nervous system of an insect. (Bedrawn from Theobald, Agrindtural Zoology ) 17 ventral, while in vertebrate animals the nervous system is dorsal and the circulatory one ventral. In insects, the nervous system is not concentrated into a large brain, but is divided among a series of nerve centres, or ganglia, arranged in jjairs often fused together. The ventral line in Fig. 11 shows the position of these ganglia and their connecting nerve cords, and Fig. 14 shows the ventral nervous system, with its small nerve-branches. The double mass shown at the extreme end, and the next portion connected by the heavy lines, together form the brain. The former portion is above the oesophagus, or gullet, and the latter below, and the heavy lines referred to are nerve cords which connect the two parts, the gidlet running through the opening thus made. The first portion of the nervous system is the suj^ra-oesophageal ganglia, the second the sub-oesoiDhageal ganglia ; these are connected by the oesophageal nerve collar. ISText follow three thoracic and seven abdominal ganglia, all connected ])y a central nerve cord. The nervous system varies according to general struc- ture, usually by fusion of ganglia ; but, with the exception of the suiDra-oesophageal ganglia, it is alwa3's ventral in position. Nerves extend to all the organs and muscles, and permit the insect to respond to a stimulus of any sort. The nerve-endings in certain insect structures, such as antennae, palpi, etc., are very delicate, and enable the insect to be conscious of very slight stimuli. Digestion. The digestive system in insects, in its simplest form, oonsitss of a cylindrical tube, extending in a direct course from the mouth to the anus. In the more specialized insects, the alimentary canal is very modified, being folded and doubled on itself in such a way as to give it a length con- siderably in excess of the total length of the body. The organs which are concerned with feeding and digestion occupy a very large proportionate part of the entire body- cavity, as may be seen b}^ reference to the drawing at Fig. 11. Food taken in at the mouth passes by means of the oesophagus, or gullet, to the stomach. Sometimes a crop and gizzard are develoiDcd— the crop for storing a portion of food, the gizzard with strong muscles and 18 chitinous ridges and hooks, by means of which the food is reduced to a finer condition before entering the stomach. In certain insects, at least, a larger part of the actual digestive process is carried on in the crop, and in these also, the gizzard serves an a strainer through which the Kner portions of the food, with digestive fluids, are carried to the stomach, in which absorption takes place. The stomach is a large digestive organ (Fig. 11) from which the food passes to the intestine, colon, rectum, and to the anus, where waste and undigested food is voided. The food canal is composed of three sections, the foi"e-gut, mid-gut and hind- gut. The manner of taking food also varies gi^eatly among insects. Certain insects with biting mouth parts, such as grasshoppers and man}' beetles, eat vegetable food, in both the larval and adult stages of their development. Others, such as plant lice and cotton stainers, take plant food by means of sucking mouth parts also during the whole of the larval and adult life. Others, still, feed with biting mouth parts in the larval stage, and in the adult one either do not feed at all, or get their food by sucking the juices of plants ^nd flowers. Many butterflies and moths are examples of these. Other examples of the variety of ways of feeding are to be seen in the mosquito, the larva of which is a scavenger or predator in stagnant water, while the adult male sucks the juice of fruits and flowers, and the adult female the blood of animals. Another example is to be found in many bees and wasps, where the same individual possesses mouth pai'ts developed for both biting and sucking. The manner of feeding has a great influence on the development of the food canal. Larvae, with biting mouth parts, which feed on vegetable matter have very large ali- mentary systems, while predaceous insects have smaller ones, and those which suck the juices of flowers and plants, and the blood of animals, smaller still. Certain insects which suck their food, such as Lepidoptera, Diptei-a and Hemiptera, have a development of the gullet which acts as a sucking- pump, by means of which the food is taken up and forced back into the stomach. In bees and ants, the region of the gizzard is occupied by the honej^-stomach, into which the nectar can be taken and kept sejDarate from the actual food of the insect. The nectar or honey can be disgorged at will. Attached to, or communicating with, the alimentary canal, there are two or three different kinds of glands, each 19 kind ill pairs or in a nnmber of pairs. The salivar}' glands open into the mouth, and in adflition to possessing the func- tion of moistening foods, they are often developed for quite different purposes. For instance, the silk glands of the silk- worm and many other caterpillars, the poison glands of mosquitoes and of certain Hemiptera are salivary glands, or portions of the salivary glands specially developed for the purpose. Other poison glands, scent glands, and glands for many special purposes occui- in insects, but quite apart from tlie digestive system. The kidney tubes, or ' malpighian ' tubes, of insects comnuniicate with the food canal, at the junction of the mid-gut with the hind-gut, that is where the stomach and small intestine join. These are often very numerous, and their function is excretory, similar to that of the kidneys in other animals. The waste products are passed into the intestine, and thence voided through the anus with the undigested food and other waste matter. Repkodi'Ctiox. Kejjroduction in insects is sexual, as a general rule, the organs of the two sexes being borne in separate individuals. Hermaphroditism (the two sexes in one individual) does not occur normally, and it is not known that hermaphrodite insects ever reproduce. The sexual organs are well devel- oped, the testes of the male producing the spermatic fluid, and the ovaries of the female, the eggs. In the female of many species, the ovipositor is developed with special refer- ence to the situation in which the eggs are to be laid. In the case of many bees, wasps, and ants, the ovipositors are often develoiDcd and used as stings, and as such are well known to most persons. Certain grasshoppers are able to force the abdomen into the ground for the purpose of egg- laying ; thrips, the cane fly and others have a saw-like organ by means of which the eggs are deposited in incisions in the surface of the plant tissue. Asexual reproduction occurs in plant lice, during a portion of the year, and in a few other insects. This parthenogenesis, as it is called, is a normal featui-e in the life-cycle, and the oifspring consists of females. The queen of the honey-bee is able to lay, at will, fertilized eggs which produce female, and unfertillized eggs which produce male, forms. Another kind of a sexual repi'oduction, known as •20 paedogenesis sometimes occurs in insects. The larvae of certain Cecidomyiidae are capable of giving birth to young, and in an another group of small flies the puj^a deposits unfertilized eggs which are capable of hatching. 21 CHAPTER IV. Orders of Insects. It has been shown ah-eady (see p. 4) that the class Insecta is o7ie of the four chisses of Arthropoda. This is divided into orders, each of which inchxdes individuals which have some prominent characteristic in common. Each order is separated from all the others by the fact that its members possess characters which are not shared by the meml)ers of any other orders. The number of orders used in any classification may vary according to the purpose for which it is intended. In the present instance, for example, ten oixlers are considered ; in a more careful analysis for systematic purposes, certain of these might be divided to form others. Cai^penter (Insectff. Their Stiucture and Life) employs fifteen orders, Comstock {Manual for the Study of Insects) nineteen, and Sharp (Tajn- hridge Natural History, Insects, Vols. V, VI) carries out the careful division until thirty-five orders are provided. When, as in the present case, only ten orders are used in the classification, some of these must include groups which differ slightly from the type of the order, bub show a decided relationship to it. Order I. Orthoptera. Straight-Winged Insects. This includes cockroaches, crickets, mole crickets, grasshoppers, leaf insects, the godhorses, earwigs, and similar insects. Insects of this order have two pairs of net-veined wings, the first pair being thicker and stronger than the second, while the latter are large and 22 more delicate, and when at rest are folded lengthwise like a fan, under the first pair, which serve as covers for them. This straight, longitudinal folding of the wings provides the name of the order, which comes from tlie two Greek words orthos, straight, and ^jferoj, a wing. The silverhsh (see Fig. 8) are for convenience included in this order, although tlie}^ are wingless. The metamorphosis is incom- ■_ Fig-. i5.'~iOrtnoptera. Grasshopper. tiliyht/y ^enlarged. (Orighutl.) plete ; the inouth parts are foiuned for biting, in both larvae and adults. The silverfish. a common household pest, which is one of the most primitive of insects, should really be included in another order — the Th ysanura. The members of this order never possess wings ; their mouth parts are formed for biting, but are not powerful ; and their metamorphosis is incomplete. Only one insect of this order is mentioned in this book ; and for the sake of convenience it has l^een referred to the Orthoptera, which include insects most closely related to the Tliysanura. Order II. Thysanoptera. Fringe-Winged Insects. This order includes the insects known as Tlirips. These are small, delicate insects with mouth parts formed for cutting and lapping. The first and second pairs of wings are similar i]i size and shape^ and are bordered with a fringe of 23 Ui) arfii/f : {/>] Fig. i6. Thysanoptera. Onion thrips. f sanir : {(') yoinn/ /arva ; (fl) full-groirn foi A/l fp-rni/i/ ni/(ir(/i'l. {Ffo))i f^.S. Dept. Agric.) fine liairs. The iiauie of the order comes from the structure of the wings, being derived from the two Greek words thf/sanos, a tassel, and j^tf'ron, a wing. Fig. 16 shows young and adult tlirlp^, the latter with its delicate, fringed wings. Order III. Homiptera. Half- Winged Insects. This order includes the true hugs, plant lice, scale insects and several parasitic forms such as the bed bugs and lice. The name of the order is derived from the Greek words /?(^/»i, lialf, and ptevon, a wing, in reference to the fact that certain of these insects have the ])asal portion of the Fig:. 17. Hemiptera. Leaf-footed plant bug. Txcke nafund size. {From U.S. Dept. Agric.) 24 Fig. i8. Hemiptera. Melon aphis. (a) iciaged female ; (aa) enlarged anfenna of same ; (aO) dark female, side vieiv, sucking juice from surface of leaf; (b) young or larva ; (c) last stage of nymph ; («) u-i^igless female. All greatly enlarged. {From U.S. Dept. Agric,) 25 first pair of wings thickened, and tlie apical portion iiiem- l)ranous. The metamorphosis in this group is incomplete ; the month parts are formed for piercing and sucking in both the hvrval and adult stages. This order includes insects showing great diversity in structure, especially with regard to wings, and in metamor- phosis. In the case of many of the plant bugs (Fig. 17) with the typical structure of fore-wings as mentioned above, the second pair is membranous, and both sexes are winged. In the case of the white Hies, cicads, leaf-hoppers and plant lice (Fig. 18) both sexes are winged, the wings of l)oth pairs ai'e membranous throughout, while in the scale insects (Fig. Ill) the female is wingless and the male is provided with only one pair of membrauoua wings. 1 a. x3. ;. ®,ji % f Fig. 19. Hemiptera. Scale insects, showing male and female scales, and a wing^ed male insect. All ciiUirgtd, {Iwprrinl Depf. Agric.) 2G Order IV. Odonata. The Dragon Plies. The dragon flies or jDond flies are familiar to all residents in the West Indies by their swift, darting flight, the apparent delicacy of their structure, and often by their bright and irridescent colours. They are insects with biting mouth parts in both immature and adult stages of growth, and they are predaceous on insects or other forms of animal life, in both stages. The immature stages are passed in standing, or slowly-running, A\-ater, Pond-flies (Fio-. 20) have two pairs of membranous, strongly nerved wings, of which the second or hind pair is often longer than the first. Fig. 20. Odjnata. Pond-flies. Botli about nfifiiraiyize. (Oriifinal.) The origin of the name of the order, which is thought to have come from the Gi-eek Avord ofhjus. a tooth, is not w^ell understood. $7 Order V. Platyptera. Plat-winged Insects. This order includes several groups of insects which were formerly considered in the old order Neuroptera. It com- prises the families containing the Termites, the biting bird lice and the book lice. The termites, or white ants, are well known (Fig. 21); the bird lice are wingless parasites of birds Fig. 21. Platyptera. White Ant. (a) adult male ; ib) terminal abdominal segments; (c) same of female, • {d) male side view; (e) abdomen of female, side view; if) tarsus showing Joints and claw; a, d,e, enlarged; b, c. /, greatly enlarged. {From U.S. Dept. Agric.) 28 both wild and domesticated, wliile the book lice are the minute, fragile insects often seen in books and old papers. The insects of this order are characterized by the possession of biting mouth parts in the larval and adult stages of growth, and two pairs of membranous wings, the two pairs being similar in size and shape. Tlie metamorphosis is incomplete. Order VI. Neuroptera. Nerve Winged Insects. In this order are included the lace-wing Hies (Fig. 22) and others similar in appearance. The principal distin- guishing features are the two pairs of membranous wings Fig-. 22. Neuroptera. L£C3-wing fly. Enlarged. {Imperi((l Di'pt. Aifric.) with many nerves or veins, and cross nerves, the conspicuous antennae, the biting mouth parts, in both larval and adult stages, and the complete metamorphosis. Order VII. Lepidoptera. The Scale-Winged Insects. This order includes the butterflies and moths. (Fig. 23.) The chief characters are the two pairs of membranous wings covei'ed with overlapping scales. The mouth parts in the larvae are formed for biting, while the adults either are not able to feed at all, or have mouth parts adapted to sucking the nectar of flowers or the juice of ripe fruits. The metamorphosis is complete. The name of the order is derived from the two Greek words lepis, a scale, and ^j^e?'OH, a wing. This order includes many pests to agriculture, such as the moth borer of the sugar-cane, the r-otton worm, the giant moth borer, the potato moth and cut worms. Nearly all the injury caused by these insects is brought about by the feeding of the larvae, (Fig. 24.) 29 Fig. 23. Lepidoptera. Potato moth. Sliyhtlu reduced. (Original.) The adults are often beautiful in their colouring and the delicate patterns they exhibit. Some of the larger of them, especially some of the night-flying moths^ are known as bats, mollv boobvs, etc. Fig. 24. Lepidoptera. Full-grown caterpillar of moth borer. Enlarged. (Imperial Dept. Agric.) Order VIII. Coleoptera. Sheath- Winged Insects. The members of this order have the first jDair of wings thickened and horny, to form a sheath or cover for the membranous second pair, which are the true wings for flight. When at rest these latter lie folded under the first pair. The wing covers (elytra) meet in a straight line down the back, protecting the wings and generally the entire dorsal surface of the abdomen. The mouth parts are formed for biting in both larval and adult stages of growth. The metamorphosis is complete. The name of the order is derived from the Greek words coleos, a sheath, and pteron, a wing. 30 The Coleoptera are the beetles, induding hardbacks, weevils and lady-birds Many insects of this order are in- jiirions to growing crops, stored grain and household sup- Fig-. 25. Coleoptera. Root borer of sugar-cane. Adult bcifle, obouf nuiural she, (Origi)U(l.) Fig. 26. Coleoptera. Lime tree bark borer. About li tim's fi^ifura' size. (Original.) plies. Th? root borer of the sugar-cane (Fig. 25), the long-horned borers (Fig. 2o). the grain weevils, and the 31 Fig^. 27. Coleoptera. A large beetle. About \\ fiiites nnf.urnl .•. caterpillars are also eaten l)y the ^^HU) fiery ground beetle (Calosoma ff^H' nilidnw - Fig. 87) which is known VMHA to occur in 8t. Vincent and Bar- iMfM buda, and by the wild bee or WV ■ -Jack Spaniard (Poliste-s anmi- \m ^ /ar/s— Fig. 38) and other related I insects. The caterpillars and pupae are parasitized by the hymenopterous parasites such as the Chalcis Hies (C. annulata), by certain dipterous flies, and the eggs are ' attacked by minute parasitic insects such as Trichogramma pretiosa, Riley, and Telenomus, of which there are several species. The Fig. 38. Wild bee or Jack Spaniard. About 1^ 1'nitrs )iittural si (Original ) accompany 11 ig illustration (Fig. 39) shows Clinlcis ovata, Fig. 39. Hymenopterous parasite. Eidanjtd. {Fruin US Depf. Ayric,) 42 an American parasite of the cotton worm, which is similar in appearance to the West Indian species. THE LESSER CDTIOX WORM (Aletiu lun'dula, Guen.). Lepidoptera. In habits and appearance, and in its manner of feeding, this insect is very similar to the preceding one. In the larval stage it differs from the cotton worm in being slightly smaller and, when nearly full-grown, in having a reddish or pinkish tinge of colour. It also hides itself more completely during the day, and it may happen that in a field where this insect is abundant no caterj^illars will be seen until one has learned to look cai-ef ully into the bracts surrounding the flower and pod. It differs also in the manner and place of pupation. The full-grown larva of the lesser cotton worm enters into the soil at the base of the plant, where it forms an earthen cell in which the pupal stage is passed. The adult insect is slightly smaller, with a suggestion of reddish or pinkish in its dull, greyish colour. The lesser cotton worm probably occurs throughout the West Indies, but in only one instance has it been recorded as being sufficiently numerous to attract attention as a pest. This occurred in Barbados in one season, and as far as could be seen, this species was the only cotton worm in a very badly infested field. This insect is controlled by the same means as the cotton worm, and is probably held in check by the same natural enemies. COTTON STAINER3 {Dysdercus spp.). Hemiptera. Cotton stainers, of which several species are known in the West Indies, are small insects with mouth parts fitted for puncturing the tissues and sucking the juices of plants. The eggs of these insects are small, ovoid, glistening objects with a smooth surface, which are dropped loosely in the opening cotton bolls or upon the ground beneath the cotton plants or among cotton seed either in the ginneries or on the ground. The young of all the species mentioned are reddish in colour, the red being often ting '^ with yellow or black. In the adult condition the species are more easily separated by their colour markings than in the immature stages of growth, 43 Fig. 40. Cotton Stainer, {I), andreae.) Three titm-ft natural size {Imperial Dept. Agric ) Dijsdevcus andreae, Linn. (Fig. 40) is found in the Northern Islands, as far south as Gaudeloupe. This species Fig. 41 Cotton Stainer. \1> (hlauncyi.) Three titn(t> natma' M,t. (Iiiii>< / lal Dept, Agric.) 44 is red in general coloui-, marked with black and white, the white markings being in the form of a St. Andrew's Cross on the wings, and white spots on tlie sides. Dysdercus delauneiji, Leth. (Fig. 41), is the common cotton stainer of the Sonthern Islands, extending in its range from Montserrat to Grenada. The general absence of white markings on the body of this insect and the presence of a wliite band on the base of the apical segment of the antennae serve to distinguish it from the preceding. In Grenada, another species {Dy^idercuH fernaldi. Ballon) also occurs. This species differs from D. delaimeyi in having the red ground colour suffused with yellow to such an extent that the yellowish tinge often predominates. Barbados is the only island in the West Indies whei-e cotton stainers are not known at the present time. The several sp3cies of cotton stainers, though differing in appearance, are all alike in habit. They feed on the growing bolls, the seed, and probably also on the leaf and tender stems of the cotton plant. It has not often happened that they have occurred in such numbers as to prove serious pests in these islands, during the past few years ; but their power of rapid increase in numbers and the absence of natural enemies give to these insects considerable importance as possible pests. It is recorded that cotton stainers were largely responsible for the downfall of the cotton industry in the Bahama Islands, some forty years ago. In addition to feeding on cotton in the field, cotton stainers swarm about all buildings where cotton seed and seed-cotton are stored, finding food and opportunities for breeding. The seed of the silk cotton tree is also a favourite food, while such plants as the musk ochro {Hibiscus Abeli)ioschits), ochro (H. escidentus), anodyne or seaside maho3 [Thespesin populn2a^, and other malvaceous plants are often found to harbour these insects Mention has been made of the injury to the plant from the puncturing of the tissues and the sucking of the juice. The name stainer has its origin in the fact that cotton lint is discoloured by these insects. The staining is brought'about by the deposition of the excrement of the insects in the opening bolls, from the crushing of them in the gins, and probably also from disease in the bolls which gains entrance through the punctures made by the insects in feeding. 45 Control. Cotton stainers may l)e controllerl by spray- ing, collecting and tra])[)iiio;, anrl much may he done by removing outside sources ol' food, as far as possible, during the season when no cotton is available for them. Spraying with any good contact insecticide by means of a knapsack sprayer would be effective, but this is an expen- sive method that will rarely be employed in the West Indies. Collecting has proved che.ip and effective. This operation is carried out by means of tins containing water and kerosene, into which the labourers jar or shake the young stainers. The insects may be attracted to bits of sugar-cane, small heaps of cotton seed, seed of silk cotton and ripe mangoes, where they may be killed while feeding by means of hot water, kerosene or crushing. Any useless plants in the vicinity of cotton helds known to harbour these insects should be destroyed, and great care should be taken to prevent scattered seed from accumulating around einneries and store-houses. Fig. 42. Fiowerbud maggot. The adult insiJct. About '5 times natural size. (Or final.) 46 THE FLOWER-BUD MAGGOT (Contarinia gossyini, Felt.). Diptera. The flower-bud maggot is the larva of a very small fly (Fig. 42) which lays its egg in the young flower buds of Fig-. 43. Flower-bud maggot. The larva. About ■!" limes nalural size. {Original.) the cotton plant. The larvae (Fig. 43) feed on the develojD- ing essential organs, causing the death of the bud, and consequently preventing the formation of the boll. The bracts sun^ounding the base of the attacked flower-bud gen- Fig. 44. Flower buds of cotton, showing flaring of bracts resulting from attack of flower-bud maggot. Beduccd. {Original.) 4? erally flare liack (Fig^. 11) instead of remaining close around the base, as in (he normal flower, and this serves as an indi- cation of attack hefore the huds drop. The adult insect, the parent fly, is so very small that it is probably never observed in the Held upon or about the cotton plants. The length of the bod}' is only about .j^'g-iji(;h and the spread of the wings is about |-inch. The maggots, which are very small (about /.^-inch in length when full-grown), are yel- lowish, or pinkish in colour, leave the bud as soon as it falls to the ground and enter the soil, where they pupate. The flower-bud maggot flrst made its appearance in Antigua at the end of 1907, where it caused very serious losses in the cotton crop at that time. It has been recorded from Antigua each year since then, but has not appeared as a pest in any other island. The attacks in 1907-8 and 1908-9 in Antigua lasted about three months -December, January and February. The attacks in the two succeeding seasons have been less severe and of shorter duration. Control. No satisfactory means of control have been devised. The practice of early planting, Avjiil^li "^^'iA allow the forming of the bolls ^before the time for the attack of the flower-bud maggot to commence, will enable a crop to be produced. The time of planting in An- tigua is influenced very largely by the weather conditions, which sometimes make early planting difficult in that island. This condition, and the habits of this pest cause its control to be a matter of difficulty. Natural Enemies. It is likely that minute hymenopterous insects prey upon the flower-bud maggot, but it is not possible to say how far they exercise any control over it. Fig. 45- Leaf- blister mite of cotton. Greatly enlarged. {From N. Y. Eyifom. Soc.) THE LEAF-BLISTER MITE (Eriopyhes gossypi Banks). Acarina. The leaf-blister mite (Fig. 45) attacks all parts of the cotton plant except the roots. The blisters which are character- istic of this mite (Fig, 47) are distor- tions or swellings, which result from its presence, and are 48 probably due to an irritation in the tissues of the plant caused by its feeding. They are lined with a thick growth of very fine hairs (Fig. 46). among which the mites live. The leaf-blister mite is almost microscopic in size. It is so small that even when very abundant the individual mites can scarcely be seen, even with the aid of a good magni- fying glass. The amount of injury done by the pest is sometimes very severe, but the loss from this cause has been less since planters and others have become more familiar with it. The leaf-blister mite first occurred as a pest of cultivated cotton in Montserrat, in 1903. It was soon afterward found to be attacking cotton, both wild and cultivated, in all the other islands of the Leeward and Windward grouj^s. It has not, however, made its appearance in Barbados.* Figf. 46. Section through gall made by leaf-blister mite on cotton leaf. Greatly enlarged. (From N.Y. Entom. Soc.) Fig- 47- Cotton leaf attacked by leaf-blister mite. A'educed. (On'fjinal ) . * Since this pamphlet has been in the press the leaf-blister mite has been found on cotton in Barbados {Feb. 1912). . " 49 Control. The leaf-l)lister mite is ))est controlled by the flestrijctiou of all old cotton plants immediately after the crop is reajjed, and the picking off (jf infested leaves as soon as they appear on the young plants. On every estate and in every district where the leaf-blister mite is abundant, there should be a ]jeriod of several weeks between the destruction of the old plants and the planting of the next crop. All wild cotton near the fields should be cut, as a further precaution. A mixture of lime and sulphur, applied as a dust on the plants, has been found useful in checking the increase of this pest in the case of serious attack on young plants. The mites are so well protected by the fh'fornuties of the plant in which they live, that they are practically out of the reach of any insecticide. Lime and sulphur \vould only come into contact with them if the mites left the galls to travel across the surface of the leaf. This would probably only happen when the full-grown mites left the old galls iii search of young leaf buds in which to deposit eggs aufl thus provide for the infestation of the developing leaves. THE BOLL WORM (Heliotlu's obf^oleta, Hiihu.). Lepidoptera. This is perhaps one of the most cosmopolitan of all insects, being found in most parts of the temperate and tropical regions of the world. It is a very general feeder, for it attacks and thrives on a great variety of plants, generally preferring the fruit to the leaves. Fig. 48. Cotton boll worm. (a) moth ; (6) larva Slightly enlnrgirl {From U. S. Dept Agric.) 50 As a pest of corn it has caused great losses in the Southern States of America, and it is known as a pest of tomatoes, tobacco, peas and beans, and many other crops, as well. The parent moth varies from a light to a dark-grey in Fig. 49. Cotton boll worm. Showing mode of attack on cotton boll. Natural size. {From U.S. Dept. Agric.) colour, and measures about U inches across'the outstretched wmgs. The female moth, which flies in the" dusk of evenhig 51 and at niorlit, lays its e^jgs scattered over the food plant. The larvae vary nnieh in colour and markings. The more conimon form is of a greyish green colour on the sides, with two darker stripes along the back, separated by a narrow light stripe. The pupa is formed in the ground, 2 or 8 inches below the surface, in a small earthen cell within which the caterpillar encloses itself after feeding and growth have been completed. The life-cycle occupies about six weeks The caterpillar tunnels into the cotton bolls (Fig. 49), com- pletely destroying the interior, and indeed often entirely consuming the contents of them. The corn ear worn (Laphj/gma frucjiperda, S. and A.) Fig. 50— also occurs as a boll worm of cotton in the West Indies. Neither of these insects is known as a serious pest of cotton in these islands, although both are known to occur, and both are pests of Indian corn. Control The des- truction of infested bolls containing the larvae wil result in reducing con siderably the numbers oi these insects. Measures for control when they attack Indian corn should also be useful for reducing their numbers as cotton pests. The use of Paris green or other arsenical poison on the cotton plants assists in the con- trol of these pests, since the larvae feed on the leaves for a short time and have to eat their way into the bolls, and they may be poisoned in so doing. Fig. 50. Corn ear worm. (a) mof/i ; (h) Jui-cn ; luj : {(■) larva ; (d) abdominal SI (lull nl nj lnrva, lateral viric ;{e) j)((2yi, hid rid linr. (cDfxvice natural size, a b,c <■ one fourth natur- al size. {From U.S. Dept. Agric.) Traj) Crops. It is sometimes possible, when the insects become numerous, to plant corn and cowpeas near cotton fields, at a time that they will be attractive to the egg- laying moths, before the cotton bolls are formed ; so that the 52 eggs will be mostly laid in these orops instead of in the cotton. These traps would be of no use unless they were removed and fed to stock, or otherwise disposed of, before the caterpillars are full-grown, so as to accomplish their des- truction. If they are allowed to remain until the moths emerge, the traps merely provide for increased infestation of the cotton. THE RED MAGGOT {Porricondyla gossypii, Coquillett). Diptera. The red maggot is the larva of a small fly related to the flower-bud maggot, and like that one, is too small to be seen and recognized. It was first discovered in Barbados in 1903, and in one or two seasons since that time has been fairly abundant. In 1905, a very large proportion of tlie cotton plants in certain fields was destroj'^ed. The red maggot occurs under the bark of the stem of the cotton plant. The maggots when full-grown are nearly ^,-inch in length and of a reddish colour. They feed upon the soft tissue of the bark and developing wood. When the feeding of these insects extends completely around the stem, it causes the death of all the portion beyond that spot. The presence of the red maggot is always indicated by a discoloured and shrunken area of bark. It hns not occurred as a pest in any of the islands except Barbados although it has been recorded from Montseirat. The attacks of this insect have been made in rather singular manner, no field or estate having reported a severe attack in two succeeding years. For its control it is necessary that any plants seen to be affected should be pulled up, or the affected jDart cut out and promptly burned. Old cotton plants should be destroyed as soon as the crop is reaped. THE COTTON APHIS {Aphis gossypU, Glover). Hemiptera. The cotton aphis is a small, greenish insect, often to be found on the under side of the leaves of cotton and other plants. It has sucking mouth parts, and when it occurs in extreme abundance causes serious injury to the plant. The aphis, plant louse or green-fly, as it is commonly called, is usually more abundant in dry, than in wet, weather. 53 Fig. 51. Melon aphis. {a) wh\ged female ; {act) enlarged antenna of same; (ab) dark female, side view, sucking juice from surface of leaf; (b) young or larva; (0) Imst etagt of nymvh ; (a) wingless female. All greatly enlarged. From U,S, Dipt Affric.) 54 Control. If it is desired to apply remedial measures for the control of aphis, spraying with kerosene emulsion or whale oil soap would be the best treatment. This insect, howeverj is attacked by natural enemies, which often are able to 'hold it in complete control. The most important of the natural enemies are the several species of lady-birds which occur in the West Indies. The spotted lady-bird (Megilla maculata, var., De Geer), and the red lady-bird (Cycloneda sanguiiiea, L.), are shown at (Fig. 52). Certain ^00 4? Fig-. 52. Lady-birds. (a) Spotted ladybird ; (b) Red lady-bird ; (c) eggs. Enlarged. (Imperial Dept. Agric.) species of aphis, are known to be attacked by hymenopter- ous parasites, and by parastic fungi. The fungi develop much more rapidly under moist conditions and would exert more influence in the control of aphis in wet, than in dry, weather. This fact, and the fact that heavy rains wash the aphis off' the leaves of plants, would explain perhaps why these insects are more troublesome in the dry season. THE CUT WORM {Prodenici spp.). Lepidoptera. (Jut worms are the larvae of certain night-flying moths There are in the West Indies several closely related species which are all alike in general habit. These cater- pillars live in the ground and feed on the roots of plants and on the stems of young seedlings. One of these, Prodenici ornithogalli, is shown in the illustration (Fig. 53). Cotton plants are often attacked, the second or third day after they appear above ground. Cut worms can be controlled by the use of poisoned bait, which is applied on the surface of the gi'ound or lightly covered with soil at the time that the seeds are planted. 55 Fig"- 53- Cut worm. Dark form, male, above; pale form, female, below, enlarged, {From U. S. Dept. Agric.) Somewhat Cut worms. form (b) dark form of larvae. {From U.S. Depf Agric.) A poison bait which has been used with good success in Barba- dos, in controlling cut worms in p-cotton fields, was made by mixing 25 ft), bran (pollard) and 1 lb. Paris green to a thick paste with water, to which a sufficient quantity of molasses has been added to sweeten the mixture. This bait is used by throwing down a small handful (one or two table- spoonfuls) at each hole when the seed is planted. The cut worms eat the poisoned mixture, and are killed before the seed- lings come up, and the injury is prevented. 56 SCALE INSECTS. Heiniptera. Cotton ill the West Indies has been attacked by two species of scale insects which are coniinonly known as tlie black scale and the white scale. The black scale {SaisseUa nigra, Nietn.) has been a very serious pest, especially in Fig 55. Black scale on cotton. Slightlij enlarged. (Oriyinal.) Barbados, whei*e in 1905, several fields of cotton were a total loss owing to the severity of the attack of this pest. At the present time, black scale attracts very little attention and has ceased to be regarded as a pest by most planters. This changed condition has been brought about by the develop- ment of the parasite of the black scale. This beneficial insect is now known to occur throughout the West Indies. ' It was first reared from the black scale in Barbados in 1907, and s]jecimens were submitted to the United States Department of Agriculture for identification. Through the courtesy of Dr. L. O. Howard, Chief of the Bureau of Entomology, these were studied by JMr. J. C. Crawford, who found the insect to be a species new to science, to which he gave the name Zalophothrix mirum. The insect is very small (about yV-inch in length), at first glance resem- bling a small ant with rather short wings. Its general colour is dark-brown, the head bearing conspicuous reddish brown eyes ; the transparent wings are ci'ossed by a broad dark band near the middle. The egg of the parasite is deposited by the female under the body of the scale insect, about the time that the latter begins to produce eggs. The parasite grub hatches in the midst of 57 the scale insect eggs and feeds upon them. Generally, only one parasite grub is to be found under each scale, but in a few instances two have been seen. When its growth is finished, the parasite changes from a fat, whitish griil) to u pupa which, when first ft)rmed, is light-coloured, and later is almost black. At the completion of the pupal stage the adult Zalophothrix emerges through a round hole in the back of the scale insect. An abundance of scales punctured in this way indicates an efticient percentage of parasitism, but it must be remem- bered that such scales are dead and that the parasites have left them. Other full-grown scales on the same plant will probably contain the grub or pupa of the parasite. In the event of an attack of black scale occurring in a iield of ycnnig cotton, it would be advisable to introduce the parasite in order that the couti-ol of the scale might be begun as soon as j^ossible. Old cotton plants in which there is an abundance of black scale should be pulled up after the cotton is reaped, and piled in the field for two weeks before they are burned or otherwise destroyed. This will give the nearly mature parasites an opportunity to emerge, and being winged, they will be able to fly into adjoining wild land in search of scales in which to deposit eggs ; many of the scale insects will die for want of food as the plants become dry, since they are not able to travel far, and the few that succeed in establishing themselves on other plants will in all probability become so severely attacked by parasites that they will be practically killed out. Fig. 56. White scale on cotton. About 1^ times natural sLe. {Original.) 58 The white scale (HemichionasjDis minor) has not often occurred as a serious pest of cotton in tlie West Indies. This is due to the fact that it is held in check by parasitic insects. The parasites of the white scale are very minute, almost miscroscopic in size, but their effect is very beneficial. The presence of these parasites may be determined by the punctures in the scales, as in the case of the black scale, and t is likely that in the event of a serious attack of this pest, parasitized material might be introduced in the same man- ner as is suggested for the black scale. RED SPIDER (Tetranyckus gloveri, Banks). Acarina. Cotton is sometimes, especially in very dry weather, attacked by a very small mite, the cotton red spider, which lives on the under side of the leaves. Enormous numbers of this mite occur on each leaf, and the effect of their feeding is to 'cause the leaves to dry up. The red spider can be distinguished only by careful examination of the infested leaves, when it may be seen actively running about often under or among the very delicate threads of a sparse web. Small patches of a red- dish coloui^, in the body of cer- tain of the mites, will jDrobably he the first thing to attract the eye to these small, but very harmful, organisms. If it becomes necessary to ^^ resort to remedial measures for the control of the red spider, the use of any contact in- secticide, or of sulphur and lime, ^. ^. . . in equal parts, applied dry as a Fig. 57- The cotton red spider. ^^^^^^ ^^,^f^ ^^ effective. In mak- Adult, '''^'^^\^'^'^i:flf' <^'S. ii,g s.^ci, an application, it must be remembered that the red spider lives almost entirely on the under side of the leaf, and therefore, it is necessary to apply the insecticides to this place. 59 ■ Up to tlio present time, tlie red spider has not been sufficiently abundant to render the application of insecti- cides necessary. THE I50LL AVEEVIL {Anthonomi(>! (jrandis, Boh.). Coleoptera. Tlie l)oll weevil of cotton is not known in the Lesser Antilles, and it is greatly hoped that it may never be in- troduced. Since this insect made its entrance to the United States from Mexico in 1894, it has developed into one of the most serious pests on record, and there seems to be no possibility of stopping its steady progress eastward to the Atlantic Coast. The accompanying figures (58 and 59) are given in order to show what the insect is like in its different stages of growth. The fine line in Fig. 58 shows the exact length of the weevil. Fig. 58. Boll weevil. Adult insect. Enlarged. (Frum U. S. Dept. Agric.) Fig. 59. Boll weevil. Larva and pupa. Enlarged. {From U. S. Dept. Agric.) 60 The introduction Antilles would in all cotton industry. of the boll weevil into the Lesser probability put a speedy end to the SUGAR-CANE. MOTH BORER (Diatraeci saccharalis, Fabr.). Lepidoptera. The moth borer is one of the most serious of all the pests of sugai'-cane in the Lesser Antilles. It is known throughout the sugar-growing regions of tropical and sub- tropical America, of which it is probably a native. It also attacks Indian corn in much the same manner as it affects sugar-cane. The parent is a whitish or straw-coloured moth, with dark spots on the wings. The wings, when spread, measure about li inches. The injury done by this pest to the cane results from the tunnelling of the larva in the stems. TJie larva of the moth borer is a whitish caterpillar with scattered dark spots, in each of which there is a black hair or bristle. When full-grown, it is about 1 to I'l inches in length. The pupa, which is formed in the tunnel made by the larva, is about |-inch in length, dark brown in colour, and the abdominal seg- ments are set with short, stiff Fig. 60. Eggs of moth borer, bristles. Enlarged. {Imx)€rial Dcpt. Agric.) The eggs of this insect are flat and scale-like (Fig. 60). They are laid on the leaves of the sugar-cane in clusters of twenty to thirty. The larva (Fig. 61), soon after hatching, travels down the leaf to its base, which in young canes is near the growing point. It bores its way into the stem, where it spends the remainder of the larval and the pupal stages. When the pupal stage is completed the moth (Figs. 62 and 63) Fig. 61. Full-grown caterpillar of moth borer. Enlarged, {Imperinl Dept, Agric) 61 emerges from the pupa case and from the tunnel in the cane. The time occupied in tlie hfe-cycle of this insect is about fifty days. Fig. 62 Moth borer. (a) female moth; (b) irint. Jgric.) Fig. 88. Citrus white fly. (a) orange leaf showing infestation oit hu'/'-/- Hurface, natural size; (6) egg; {c)same with young insect emerging; id) l(trr;i.; [r) foot of same; (/) larval antenna ; (g) scale-like pupa; (h) pupa about to disclose adult insect; (i)insect escaping from pupal shell ; ij) leg of neidy emerged insect not yet straightened and h:irden"d. All fi(iures except (a) greatly enlarged. (From U.S. Dejyt. Agric.)' 81 Indies, and these have heen referred to as the citrus white fiy, but tliere is some likelihood that a more careful study of these insects will demonstrate that the West Indian white fly is the same as a new species recently discovered in Florida, and which is much less serious as a pest than Aleyrodes citri. The new sjDecies referred to is Alei/ivdes nubifera, Berger. Specimens of white fiy fairly common in Barbados have recently been identified by the state entomologist of Florida as Aleyrodes nuhifera. Another species (^4. hoivardi, Quaintance) is also known to occur on citrus plants in the West Indies, and it may be one of the species found in the Lesser Antilles. White fly is attacked by the red-headed fungus, Sphaevostdbe coccoph da, ) alveady mentioned, which occurs in the West Indies and in Florida, and also by several species of , parasitic fungi. If it becomes necessary to spray for the control of white Hy, a whale-oil soap solution will be found very effective. BARK I50RERS {Leptostyhis prcieniorsiis). Coleopt^ra. Citrus trees are often attacked in the stem near the ground, and wherever, in pruning, stubs have been left which have decayed, by grubs which tunnel in the soft wood underneath the' bark. These grubs are the larvae of long-horned bettles, one species of which has been identihed as Leptostyliis jyraemor.sus (Fig. 89). The grub is whitish, with a small l)rown head, and very much flattened in appear- ance. The beetle is brownisli with long slender antennae. Fig. 89. Lime tree bark-borer. About 14 times natural size. (Original.) 82 It is probable that tlie eggs of the bark borer are laid only in dead or dying portions of the trees, but it is also likely that the grubs, by their feeding, very often increase the amount of dead wood and hasten the death of the tree. Bark borers can often })e located by the dead and shrunken patches of bark. They can be dug out with a knife and the wound thoroughly cleaned and tarred, or th:-y may be killed by probing with" a wire, or by the use of car- bon bisulphide, injected into the tunnels of the borers, A small weevil of the genus Cryptorhynchus (Fig. 90) has been reported as a borer in the stems of orange trees in Grenada. This insect can hardly be called a pest, since its occurrence is compara- tively rare. In the event of vrt5Tmra>, lai'ge cultivations of oranges Nia^ftTttii; being established, however, the ''^^l&.:?^n^!''^:^r' possibility of a very rapid increase in the numbers or the l)orer should be kept in mind. (Imperial Dept. Agrk.) THE RUST MITE [Phytoplvs ohivovxis, Ashmead). Acariua. The rust mite is not of very common occurrence in the West Indies. It is a small mite similar to the leaf- blister mite of cotton. It feeds on the skin of limes lemons and oranges, producing in the ease of the latter a russet appearance, and in the case of limes and lemons a silvery appearance of the skin. Dry flowers of sulphur, used pure or with equal amounts of lime, is the remedy employed in Florida when it becomes necessary to control this mite by artificial means. This insecticide would probably be found satisfactory also in the West Indies ; it is applied after rain, or in the early morning while the foliage is still wet, being broadcasted from the hand. Bengal beans have been much used for the control of scale insects and the general improvement of lime trees in Montserrat. The beans were planted, about four to each tree, and allowed to grow and completely cover the trees. The accompanying illustration (Fig. 91) shows the appearance of a field covered in this manner. 83 Good results have been obtained iii this way, but it is not known exactly what is the effect of the Benjijal bean. Generally it is entirely beneficial and much more so than would be expected merely by the increase of the natural enemies, which has been supposed to be the chief result of the use of the Bengal beans. In a few instances, in a wet season and in damp situa- tions, harm seems to have resulted from too heavy a cov- ering of Bengal beans. 84 THE FRUIT Fi.iES. Diptera. In niauy parts of the world where citrus fruits are grown, fruit flies are very serious pests. These are Dipterous insects of several species, possessing very simi- lar habits and life-histories. In general, the eggs of the fruit flies are deposited in or on ripening fruits. The maggots, on hatching from the eggs, tunnel into the tissues of the fruit and cause it to drop and decay. The Mediterranean fruit fly (Ceratitis capitata, Wied.)— Fig. 92— is perhaps the most widelj' distributed of Fig. 92. Mediterranean fruit fly. (a) adult insect ; (e) larva ; other letters refer to structural details. All enlarged. (From U.S. iJept. Agric.) the fruit flies. The Mexican fruit fly or orange worm (Try pet a ludens, Loew) — Fig. 93 — and Dacus Trijoni, Frog- gatt, of Australia, are also very serious pests. Fig. 93. Mexican fruit fly. Adiilf femnlr. Enlarged (From V. S. Ihpt. Agric.) In tlie Lesser Antilles, citrus fruits do not seem to be attacked to any extent by fruit flies, although other fruits such as guavas and sapodillas are often found to be ' wormy ' or infested with the maggot of a species of Anastrepha. one of which is A. serpentina, Wied. Figf 94 Mexican fruit fly. Ut)larva, (c) pujnn utm , {!', d <,,,d , ) .-ifrticfHral drfails All enlarged {Fruin U.S. JJrpt. Ag^ic.) 8(3 CACAO. FiR"- 95- Cacao beetle. THE CACAO BRKTI.E (Steircistoma dcprcsPAnn, L.). Coleoptera. The cacao beetle (Fig. 95) is perhaps the most serious insect pest of cacao in the West Indies. The egg is laid in ^d^ or on the bark, often in the angles _/S^2^\J formed by the larger branches. Stubs left in pruning, and any wound of a tree, Feem to attract the egg-laying females. The grub reaches a length of about It} inches when it is full-grown. It is whitish in colour with a small, dark-brown head. The pupa is formed in the tunnel made by the larva. The adult is a black and grey beetle about |-inch in length, with long, slender antennae. The location Adult (fnd lay ra. X((turalsize. of the grubs luider the bark of {fiiiperUd Dfjif. A'jrir.) the cacao tree is often indicated by a dry, shrunken appearance. Control. The grubs of the cacao beetle may be dug out, or killed by probing with a wire. Carbon bisulphide may also be found useful in this conuexion. When the beetle gvxxhs are dealt with, all dead bark and wood should be removed and the healthy wood which is exposed should be larred or painted. The adult beetles may be trapped. In the early morning they may often be found resting on the trunks and larger branches of the cacao trees where they may be collected, and killed by throwing them into watei" to which a small amount of kerosene has been added. In Surinam, the bark of the silk cotton tree is tied on to the cacao trees to furnish hiding places for these beetles. These hiding places are examined regularly and the beetles collected. In Trinidad, trap pieces of the Wild Chataigne or ' Chataigne Moron ' (Pachira aquutica) have been found very useful. The freshly cut pieces of Chataigne ^hich are placed in the cacao tree provide the female beetles with a suitable situation for egg laying, and the eggs are laid in the traps instead of in the cacao trees. In Grenada, branches which are removed from tlie trees in pruning are left on th^ ground for a few days. 87 These branches attract the ep:g-laying females, and are afterward collected and burned. It must always be remembered, however, that when traps of this sort are provided for insects, it is necessary that they 5-hould be disposed of before the insects have an opportunity to become nmture, and escape. All woiuids made in pruning ai-e carefully tarred or painted, so that they shall offer no attraction as places for egg-laying. CACAO THRIPS (Heliothrips rubvocincta, Giard.). Thysanoptera. Thrips are small insects which attack the leaves and pods of cacao, and sometimes occur in considerable num- bers. The epg is deposited in the tissue of the plant by means of the saw -like (wipositer with which the female is provided. The adult insect is .Vinch, or less in length, and has wings fringed with long delicate hairs. (Fig. 96). Fig. 96. Cacao Thrips. Adult iitsi'cf. hnlarged. (Imperial Dept- Ap-ic.) The young (F^ig, 97) is distinguished by a bright-red band across the abdomen. Cacao is injuied by the feeding of the thiips, which have mouth parts adapted for piercing or cutting the surface and sucking the juice from the tender tissue beneath. Wherever these feeding wounds occur, a scar is ])roduced. This is especially noticeable on the iJods, a badly attacked pod being discoloured by this 88 Fig. 97. Cacao Thrips. Immature insect. Enlarged. [Imperial Dept. Agric.) means to such an extent tbat unripe pods often appear ripe. The young, tender leaves of cacao are also attacked by thrips. Fig. 98. Beetle which eats cacao leaves in St. Vincent. Enlarged ahuiit H times natural si'^e. (Original.) Serious attacks of thrips seem to occur most generally when some condition of soil or climate is unfavourable, Careful attention to drainage, the application of manure, and the addition of humus to the soil will often be found quite satisfactory in dealing with this pest. If it becomes necessary to spray, rosin wash will be found effective. 89 Cacao is attacked by apliis, mealy-bugs and scale insects. These are not often seiious jiests. The aphis sometimes is seen in considerable numbers on the young tender leaves. Mealy-bugs often occur on the pods where two pods ai'e touching, or where a pod rests against the bark of the stem. Aphis and mealy-bug may be controlled, if necessary, by spraying with kero- sene emulsion or whale-oil soap solution. Cacao is not often attacked by scale insects, but this has happened in a few instances. In a mild attack scale insects could be controlled by spraying, but if a tree becomes thoroughly in- fested, it may be better to cut the plant down and burn it The root borer of the sugar-cane lias been reported as attacking cacao in St. Lucia, especially where the crop is growing on lands formerly devoted to sugar cultivation. In St. Lucia and St. Vincent, beetles have been found from time to time eating the leaves of young cacao, and they have caused considerable damage. Xo satisfactory remedy for the root borer and the leaf-eating beetle attacking cacao has been discovered. One of these insects is shown in Fig. 98. Fig. 99. Corn ear worm. (a) Moih, (irp>iform; (h) fore wing of the more ornamental form; (r) larca; (d)ahdomtnal segment, of larm, lateral metv ; (e) pupa lateral ciev ; (d) twice natural size. Others enlarged one-p>urth. {From U. S. Dept. Agric. 90 INDIAN CORN. Indian corn is attacked by the moth borer (Diairae saccharalis) in a manner very similar to that in which it affects sengar-cane. The corn ear worm (Lophygma frtif/ipfrda. S. and A.) ■ — Figs. 99 and 100— and the boll worm (Helioihis obsoleto, Hiibn.), both of which liave been mentioned as pests of cot- ton, attack the developing ears of coin, and often canse a very considerable amount of damage. The eggs of the boll worm are laid singly on the tassel and silk of the corn, and those of tlie corn ear worm on the leaves, in clusters. (Fig. 100.) =VV^ c Fig. 100. Corn ear worm {a) E(iy from side in vpiwr figure, from nhoi-e, in the lover, ('») eii) someirhdt enlarged. {From U. S. Dept. Agrir.) If the caterpillars are present before the ears form, they begin feeding in the centre or throat of the plant. The injury to the young leaves is plainly to be seen when these have developed, in the ii regular holes and ragged edges which so often appear. Later in the season the caterpillars attack the cars, entering at the silk end (Fig. 101), Here they eat the young, tender grain, sometimes destroying more than half the entire ear. The caterpillars of both these si)ecies are cannibals to a certain extent, for when two caterpillars come together in the course of their feeding, especially when in the car, one is almost certain to kill and eat the other. Both these insects liave a very wide distribution throughout the West Indies. The boll worm is known in nearly all parts of the world, and the corn ear worm extends its range throughout the warmer parts of Ameiica. Control. It is a common practice in the West Indies to drop a little fine dust or ashes into the throat 91 of a corn plnnt ns ^oon ns the fiist sipns of attack ai'e observed. Paiis green and lime have been tried for this l)nrpose, bnt they very often injure the leaves of the corn. A mixture off teaspooonfnl of Paris green and 1 quart of corn meal lias been found useful. A small (juantity of this mixture is applied in the middle of the roUed-np leaves ; it is eaten by the caterpillars and does not seem to injure the plant. Fii^ loi Cotton boll worm. Shn,r!nym„dcnfuffu,hmji<() of, „n. {From US. Dept. Atjrir.) Early planting is said to be of advantage in this con- nexion, as in this case the corn is very rarely attacked to the same extent as when it is planted late. Guinea corn is also attacked by small grey moths which infest the ripening heads of grain, sometimes completely spoiling them. This form of injury has been reported from Nevis in an experiment plot containing a very close-headed variety of Guinea corn. The only method of prevention in such a case as this would be the cultivation of a kind with a ver}^ open head. 92 ARROWROOT. THE ARROAVROOT WORM (Calpodes ethlius, Cramer). LepirlojDtera. The larva of this insect, which occurs thi^oughout tlie American tropics, feeds on arrowroot and canna. The eggs are laid on tlie leaves of the food plant, and the larvae, as soon as hatched, begin feeding, protecting themselves from view in a fold of the leaf, which they make by drawing over the margin of the leaf and tying it down with a piece of silk. The caterpillars are greenish in colour, and very delicate in appearance. The skin is so thin that it is possible to distin- guish a good deal of the internal anatomy. The caterpillar has a very peculiar appearance on account of the small neck which is characteristic of the insects of this grf)up. The adult (Fig. 102) is brown in colour, with angular white spots in the wings, the under surface being lighter than the upper. Fig. 102. Canna Moth. Xiifurid .s/vc. [Oili/mal.) This insect belongs to a group of the Lepidoptera called skippers, which is intermediate between the butterflies and the moths. The most prominent characters of the group are the clubbed antemiae terminating in a fine hook in the adult, and the broad head and small neck in the larva. Control. The eggs of tlie arrowroot worm are para- sitized by a minute hymenopteron (probably Trichogramma pretiosa), and it is likely that blackbirds, and the predaceous wasps, such as the wild bee and others attack the larvae. 93 Paris f^reen, applied dry as for the cotton worm, will be found satisfaftory for tlie control of this insect, when it occurs in sufficient abundance to render necessary the use of insecticides. TOBACCO. THE TOBACCO WORM yPi'ofopavce Kcvta, Johanssen). Lepidoptera. The leaves of the tobacco plant are often eaten by large green caterpillars, with obli(iue, whitish bands on the sides. The adult insect is a hawk moth, grey in colour with dark-brown or black lines marking wings and body. The spots, ranged in a row on each side of the abdomen, are yellow in colour. The northern tobacco worm {Proto- parce ccleus) shown in Fig. 103, is similar in general appearance to the West Indian species. Fig. 103a. Northern tobacco worm. Moth. Natural she. {From U.S. Dept. Agrk.) The female moth deposits the eggs singly on the leaves and other parts of the plant. The full-grown larva reaches a length of 2| to 3 inches. The pupa is formed in the ground. The developing proboscis in its protective covering forms a sort of handle, which is a characteristic feature of insects of this group. 94 Control. The tobacco worm may be controlled by the use of Paris green or lead arsenate, the latter as a spray in water at the rate of 2 It), in 50 gallons of water, or the former applied dry, in a mixture with lime at the rate of 1 lb. to 5 or G lb. of lime. Fig. 103b. Northern tobacco worm. Pui>n. Natnial si:r. {From l\ S. Dept. Aijrlc.) Hand picking is very eflicient, because the caterpillars are large enough to be easily seen, and this is not very expensive in localities where labour is fairly abundant. Fig. 103c. Northern tobacco worm. Full-grown larva. Natural size, {From U. S. Dept. Agric.) 95 The natural enemies of the tobacco worm probably exert a strong influence on the abundance of this insect, although definite knowledge on this point seems to be lacking. The parasitic fly (Stiirmia distincfa, Wied.) is known to attack the potato worm, and is probably one of the natural enemies of the tobacco worm. CUT WORMS. Young tobacco })lants are often destroyed by cut worms (see Fig. 104) soon after being planted in tlii^ field. Tliese are the same as, or similar to, the insects mentioned in connexion with cotton and would be controlled in the tobacco field by the use of poison bait in the same manner as in the cotton field. THE FLEA BEETLE {Epitrix pcivvula, Fabr.). Coleoptera. The flea beetle (Fig. 105) is a small baetle with the hind legs adapted for jumping ; it is from its possession of c Cut worm {a} laro't ; {b) moth. Ndfural si:. {U.S. Dept. At. Agrlr.) 1^ rlisseiiiinati'd l)y mosquitoes, and it has not yet been proved that any of tliese diseases can he ('onununicated to human l)eings in any way except tln-ou: water, on the sui-face of which the eggs (Fig. 13ti) are laid. The larvae live in the watei- as wriggleis or ' water-worms ', and the pupae, which differ slightly in appearance from the larvae, ai-e also found A'f/r/ Fig. 136. Mosquitoes. If. irifli rii/anjrd njij.s III Ji'fl. Yniniij hiri Eiiliirijiil. {Frmii '/'. .v. Dipt. Agric.) bcloir. 122 in water. The larvae (Fig. 137) and pupae of mosquitoes breathe by means of air-tubes, and it is necessary for them to come to the surface in order that these tubes may come into contact with the air above. In the illustration the FiR- 137- Larva of mosquito. {Frotn U. S. J)ept. Agrlc.) breathing organ is shown as a projection at right angles to the main axis of the body. Control. In order to get rid of mos(|uitoes, all stag- nant water should be done away with as far as possible. All old tins, bottles, etc., should be removed ; pools should be filled in or drained. Water tanks should be screened in such a way as to prevent the entrance of the adult mosquitoes for the purpose of egg-laying. Many plants are able to hold water in sufficient quantity for the breeding of mosquitoes, and these should Ije destroyed. Ponds and streams which cannot be done away with should be stocked with millions (Girardinus poeciloides, De Filippi) or other small Ksh, (Fig, 138) and these will also be found efficient Fig. 138. Millions. Enlarged. {Imperifd Depi. Agric.) in the case of garden tubs, fountains, etc., where ornamental plants are grown, as well as in cisterns and tanks which cannot be screened. Kerosene, sprayed on the surface of any water in which mosquitoes are breeding, is a very eflficient means of destroying them. When the mosquito larvae or pupae rise to the surface to breathe, the kerosene 123 comes into contact with their air tubes and causes their death. It may he mentioned tliat only the female mos- quitoes ai'e capable of piercing the skin and sucking the blood of animals. The mouth parts of the male are adapted for sucking the juices of Howers. The attacks of the adult mostjuito can be prevented by the use of moscjuito nets over the beds, or by screening doors and windows of dwellings. The use of citronella oil, lavender oil, eucalyptus oil, and other strongly scented substances will often be found efficient in keeping away these troublesome insects. Tt is sometimes desirable to rid a house of mosc^uitoes and this can be done by fumigation. The fumes of sulphur or pyrethrum, or of a mixture of carbolic? acid and camphor, will accomplish this object. In order that fumigation may be effective, however, it is necessary to be able to close doors and window.s, so as to produce practically air-tight rooms or an air-tight house. Strips of paper pasted over cracks aufl crevices are very efficient in preventing the escape of gases durine fumigation. FLEAS. (Pulex spp.). Diptera. The house-flea {Pulex irritans) sometimes occurs in sufficient numbers to cause it to be considered as a pest. Pig- 139- House flea. (a) larva; (b) pupa ; (c) ctdnlf flea. All enlarged, (From U. S. Dept. Agric.) m The eggs are deposited in corners, crevices in the floors and walls, nnder carpets and in similar locations. The larvae, which are minute worm-like maggots, (Fig. 139) live among the dust and dirt, and are said to feed on the particles of organic matter found in such places. The adults hide in clothing and bedding and attack hunuui beings, principally at night. The mouth parts are especially adapted for piercnng the skin and for sucking up their food, which is the blood of the victim attacked. The length of time required for the complete life-cycle is al)out four weeks. In order to rid a dwelling of fleas after it has once become infested, it is necessary to remove the breeding places. In such a house it wf)uld be advisable to remove all carpets, rugs and floor mattings, and to have these thoroughly cleaned by beating and sweeping, out of doors. Floors should be swept and scrul)l)ed, and great care taken to prevent the accumulation of any dust and dirt. Pyrethruin is ver}^ effectual in destroying fleas, and may be dusted in all places frequented by the adults, or in which the lai'vae are likely to breed. Powdered alum is said to be an effective remedy for fleas. This may be dusted in the same way as is mentioned for pyrethrum, or it may Ije dissolved in water, and the solution used foi- wiping floors. When it is found that beds ai'e infested with adult fleas, the following simple method will probably prove veiy effective. Take an old sheet, and wring it out in a strong solution of alum and water and thoroughly dry it. Spread this over the mattress and under the sheet that is slept on. The cat and dog flea (Pulex seri-aticejjs, Gerv.) also attacks man, and the methods of control just mentioned will be found useful for these insects. (See Fig. 148.) Fleas have long been known as insects which cause irritation and annoyance, but (|uite recently' it has been discovered that certain species of these insects play an important part in the transmission of one of the most serious of disea.ses— bubonic plague. It has been found that rats are the means l)y which plague is spread. This disease attacks rats, and is communicated to the fleas which infest them. When a rat dies of jjlague. the infested fleas leave the dead body in search of other food, and if these insects bite human beings the disease is communicated. In addition to the killing of the fleas, it is necessary to destroy the rats also, in order to control an outbreak of plague. ]Most persons will hai^ly distinguish between different kinds of 125 Heas ; tlieivfoi-e all Heas should be tivated with suspicion and the greatest care exercised to ))reveut tlieir occnu'reuce. TH K CHKiOE ( )R .) IG(i ER KLEA {Sdi-ropst/Ua penetrfois). Diptera. This insect is probably a native of tropical America, and it attacks a great variety of domestic animals, in ad- dition to man. The adult fleas attack their host in the same way as the house Hea. In addition to this, the adult female burrows into the skin, especially miderthe toe nails, between the toes and in any crack or crevice of the skin or flesh of the foot. As the eggs develop, the body of the female increases greatly in size initil it becomes a nearly spherical object, sometimes as large as a good-sized pea. This growth of the body of the flea is accompanied by itching, severe pain and swelling, sometimes resulting in a very serious ulcer. The jigger should be removed from the flesh as soon as its presence is discovered, great care being taken to remove the insect entire, since the bursting of the body, and the discharge of the eggs in the flesh of the host is likely to produce a serious sore. To accomplish this, a slight incision should be made with the point of a sharp, clean knife blade and the flea carefully worked out by pressure at the sides. THE HKD BTCi (Ciiur.r lecixdarid, L.). Heniiptera, This disgusting and annoying insect (Fig. 140) is widely (fi) ti'hdf 0 Fig. 140. Bed bug. ■■(/)'il nith blnod ; (h) s frt {From U. ,S. Dept. Agric.) >)ii heloir. Enlarged, 126 distributed throughout the tropics, and probably thi'oughout tlie entire inhabited world. It is a flattened, brownish, ovoid insect, without wings and with mouth parts well adapted for piercing and sucking. It is very easy for a house to become infested with the bed bug and very difficult to free it from the pest. Their flattened structure makes it possible for these insects to hide in the smallest of crevices, and they secrete themselves in any cracks or joints in the framework of beds. They also hide in cracks in tlie floors and walls, behind wall- paper, and in mattresses and pillows. When it is discov- ered that bed bugs have become established in a bed, the following procedure should be adopted. The linen, mattress and pillows should be taken out of doors and carefully searched for any of these insects. Every possible hiding- place such as seams, hems, and the knots with which the mattress is tied, should be carefully examined and bruslied with a stiff brush. Sheets should be brushed and hung up in the sun, and pillows should be examined as carefully as the mattress. The frame of the bed should be taken apart, and every joint and crevice and the springs examined. If bed bugs have been established for any length of time, their hiding places will be revealed by discoloured spots caused by the excrement of these insects, by their cast skins, and the empty egg shells which are pearly white in colour. Kerosene and turpentine are excellent insecti- cides for the destruction of this pest. These should be applied liberally wherever any signs of bed bugs are seen, and it would be well to soak thoroughly every joint and crevice in the structure of the bed and the springs. This examination and treatment should be repeated three times at intervals of a week ; and if the insect makes its re- appearance later, the entire course of treatment should be repeated. Iron bedsteads are greatly to be preferred to those made of wood, as they offer fewer opportunities for bed bugs to hide. Bed bugs have the power to live for long periods, under conditions which make it impossible for them to obtain human blood for food. Old beds which have been stored for some time, away from any sleeping apartments, have been found to be infested and those which are used only for short periods separated by long intervals, have been known to contain the insects, which in these situations are, as might be expected, most voracious. The traveller in the tropics 1^ would do well always to be provided with a good supply of pyrethrum or similar insect powder. A little of this substance, dusted over sheets and pillows, may })rovide against attack by both bed bugs and Heas, and aid in procuring undisturbed rest. lAVE. Hemiptera. There are three species of parasitic Hemiptera known as lice, which are peculiarly adapted to life on the human subject. These are the head louse (Pedicnht.s aipitin, De Geer), the body louse (PediciduN ve.sthnenti, Leach) and the crab louse ( Phthirius ingtiinali% Leach). The first two of these are similar in appearance and in habits. The former, however, lives only in the fine hairs of the head, the latter secreting itself in the clothing. The crab louse is smaller and broader in proportion, than the others, and it inhabits the coarse hairs of other parts of the body than the head. The eggs of lice, commonly called nits, are small, whitish, ovoid objects attached to the hairs, or, in the case of the body louse, secreted in the folds of the clothing. The remedies to be used for the control of these para- sites are, first, cleanliness, and second, the destruction of the insects by means of a contact poison, or in the case of the body louse, by the fumigation of the clothes. The contact poisons to be used include insect powder, oils and oily mixtures, mercuric ointmetits and sulphur ointment. The body louse occurs chiefly among armies and in prisons. Infested clothing may be subjected to baking or to treatment with the furnes of sulphur or tobacco. If this treatment is repeated two or thi'ee times at intervals of a few days, and strict personal cleanliness is maintained, the attack by this insect will probably be overcome THE BLOOD SUCKING CONE NOSE {Conorhinus scmgumiga, Lee. ). Hemiptera , This insect, which is sometimes called the big bed-bug (Fig, 141), belongs to a family of Hemiptera which includes ^iis Ui) larvn Fig. 141. Blood-sucking cone nose. {!)) (idiiU. ?:nknyff/. {Fro»i U. S. Drpf. Agri several forms predaceoiis on otlier insects. The IjIocxI- sncking cone nose feeds generally on other insects, but the winged adult sometimes Hies into houses at night, and if opportunity offers attacks sleeping per.sons. The •strong sucking mouth parts with which the insect punctures the skin of its host for the pnrpo.se of sucking )>lood is capa- ble of inflicting a very painful wound. Cases are known of fever and severe illness, accompanied l)y swelling and in- Hammation in the vicinity of the bite, following the attack of the blood sucking cone nose. The insect is about |-inch in length, of the typical appearance of the Hemiptera, the wings lying along the Imck. being narrower than the ab- domen,' the edges of which are marked with alternating- areas of red and black, which latter is the general grounrl colour of the entire insect. THE HorSE FLY (Mukcci cJoniesfica). Dipt era. The liouse tly (Fig. 142) is probably to be considei-ed as much a household pest, .is a pest attacking man. Within the past few years, however, the agency n\ this insect as a carrier of typhoid fevei- has come to be so well known thai it is included in this place rather flian among the householcj pests, , 129 Fig. 142. House fly. Pupnrhon at left ; adult next; larva and enlarged parts at right, Eidarged. {From U. S. Dept. Agric.) The house Hy breed in manure and de(;ayincr organie matter. Its life-cycle occupies a very short time and the females deposit a lar^e number of eggs, thus providing for very rapid increase in numbers. House flies visit the most repulsive and unclean situations and, if opportunity offers, they go from these places directly into houses, mess tents, etc., Avhere they walk about over food stuffs, contaminating them with any disease germs oi- hlth which may have adhered to the hairs of their legs and bodies The house fly is dis- tinctly a creature of hlth and uncleanliness, and the first step toward ridding a house or locality of these undesirable visitors is to remove the material and the conditions which provide them with breeding places. Under estate conditions and in stables, manure may be treated with gypsum or air-slaked lime and thus be ren- dered unsuitable as a breeding place for flies. BETE ROUGE (Tromhiclium sp.). Acarina. This small mite occurs in some of the West Indian Islands in such abundance as to cause it to be considered a pest. There is a great difference, however, in the degree of susceptibility to attack, some persons being frequently and seriously annoyed by these small creatures, while othez"s will very rarely notice them. The bete rouge is knoWn as the harvest bug, and in some localities is called a chigger. 130 They are minute reddish mites which occur in grass and shrubs. They attack the ankles and wrists of persons who are exposed to them, and if left undisturbed will bury them- selves in the skin. When they occur in great numbers as they sometimes do, and swarm o\'er the arms and legs, they cause an extremely painful irritation. These small mites have been described and figured as species of the genus Leptus — Leptns trritans, and L. ameri- cana — but they are probably only the larval forms of some Trombidium. Several remedies are in use in the tropics against this mite. The wearing of thick boots, riding leggings, or put- ties, will often serve as a preventive, especially in short grass. The application of rum, whiskey or dilute alcohol will Idll the bete rouge, if this can be made before the mites have burrowed into the skin. Lime juice and greasy substances, especially carbolated oil, vase- line, or tillow candle will generally be found etfective. An effort should be made to prevent mites from burrow- ing into the skin. They can often be discovered in the centre of the little red swelling which results from the irritation caused by them, and if they are removed much of the irritation may be avoided. 131 CHAPTER VII. Insect Pests of Domestic Animals. Domestic animals in the tropics are attacked by insects and other pests to an extent perhaps greater than is the case with similar animals in cooler climates. In the small islands of the West Indies, however, certain of these pests are less troublesome than in larger tropical countries and in temperate and sub-tropical i-egious. Tlie cattle ticks are an example of such pests. In some parts of the world the cattle ticks are the cause of great loss to cattle i-aisers and estate owners, because of the irritation to the cattle and the loss of blood taken as food by enormous numbers of these parasites, and also on account of the diseases which they transmit from one individual to another. Certain species of ticks also transmit diseases of goats and of dogs. Other pests and parasites injure the host animals lorincipally by feeding on the blood, which they suck by means of the specially adapted mouth parts. Fig. 143. Cattle tick. Feutale at the left, )ivdc (it the rir/ht. Enlarye {Fi-oiii U.S. Dept. Agric.) 132 TICKS. Acarina. The cattle tick {Marqaropuf^ annulatiis mistralis) occurs throughout the West Indies, It is one of the mites, and not a true insect. The adult (Fig. 143) is reddish-brown in colour ; the skin or integument is leather}' in textvire ; the number of legs is eight. The length of a large female is about |-inch. The male is smaller and flatter than the female, which when fully fed is very much distended. The immature ticks are similar in general appearance to the adult male, being small and flat with comparatively long legs. The newly hatched larvae have only three pairs of legs, the fourth pair being acquired at the first moult. The replete egg-laying female, as seen from above appears to be nearly all abdomen, the head and thorax being represented by a very small area at the anterior end of the body. The eggs (Fig. 144) are laid on the ground, each female producing great numbers — from 1,500 to 3,000. The young, six-legged larvae cluster upon grass and low herbage, where they await the passing of cattle or other ani- mals to which they may attach themselves. As soon as these 'grass ticks' or 'seed-ticks' flndthem selves on a suitable host, they insert the mouth parts and begin at once to feed. These ticks do not leave the v^ 'f'^.-z 7 V Iwst animal until the life-cycle is ±emak tick aepositiwi ^ . ,^ i. i "^ eggs. Natural size: complete; they moult, become sexu- (jProTO U.S. Dept. Agric.) ally mature, the union of the sexes occurs, and then the female, ready to begin egg-laying, drops to the ground. The time occupied by the West Indian cattle tick in completing its life-cycle does not seem to have been worked out, but, in the United States, Margaropus annidatuH has been foxmd to require about 6 or 7 weeks, divided as follows : — The first (larval) period occupies 6 or 7 days, the second (nymph) also 6 or 7 days. The adult remains on the host another 5 days, during which time mating occurs, and at the end of this, the impregnated female drops to the ground. Another 3 days ensues before egg-laying begins, and the time required for the eggs to hatch is about 21 days. 133 Since development is, in general, more rapid in the warmest weather, it may safely be assumed that the life cycle of such a closely related species or variety would not be longer in the West Indies than in the case of M. annulatus in the United States. Control. In the United States, a system of control has been demonstrated, which consists of enclosing cattle in one place while the ticks are dropping, and removing them to another before hatching commences. They are removed from the second enclosiu-e before the eggs from the dropped females begin to hatc-h. If the cattle are by that time tick- free the}' may be allowed to range over any pasture on which there has been no cattle or other tick hosts for a period of some six months. Newly hatched ticks are able to exist for about two weeks without food, after which time they die of starvation. Where a few cattle are to be dealt with, they may be sprayed or washed with a good contact insecticide. In treating larger numbers they may be dipjDed, in large vats built for the purpose. There are on the market several cattle dips and washes, especially adapted for treating ticks. These generally con- tain some oil or soap, and may include also arsenic. The following mixture has been tried on a small scale, on a cow, and found satisfactory. One gallon of kerosine, 1 gallon of cotton seed oil, and 1 &. flowers of sulphur were thoroughly mixed, and applied with a coarse cloth. The cow was washed, care being taken to ensure that the mixture came into contact with every part of the animal's skin. After an interval of a week or ten days, the applica- tion was repeated. These two applications were successful in removing all the ticks, and although the hair came off in a few places, the animal seemed to suffer no inconvenience. In adopting this method the animals should be kept on a tick-free pasture after the first application, in order to prevent re-infestation. Cattle ticks also attack horses, goats, and dogs; but not often in sufficient numbers to be considered pests. Dogs also are attacked by the dog tick which is probably a species of Rhipicephalus. The gold tick (Amblyommi variegatiim) which occurs in Antigua is remarkable on account of its larger size. It ig 134 suspected of having an influence in the spi^ead of a skin disease of cattle which occurs in that island. FOWL TICKS. Fowls in the West Indies are often attack- ed by the fowl tick (Argas miniatus) which though fairly abundant is not familiar to many persons. This is a fiattish, mottled, grey tick which hides in crevices under boards and similar situations, coming out to prey upon the fowls at night. Control. Fowl houses shovxld be built in such a way as to provide the fewest possible hiding places for the ticks and other pests of fowls. The free use of lime, or of a mixture of lime and sulphur in equal parts, dusted in all cracks and crevices, is a great aid to cleanliness from pests of this kind. The perches on which the fowls roost might be protected by means of a liand of tar or other sticky substance, applied near the ends of the perches in such a manner as to prevent the ticks from gaining access to the fowls at night. These ticks are able to live for many months without food, and the fact that a fowl house has not been in iise for a year, even, v/ill not be a guarantee that it contains no ticks. THE SCBEW WORM {Compfi geminata) which sometimes becomes very abundant, are perhaps two of the most common. The mad or crazy ant (Prenolepis longi- cortiis), which is a slender, black insect with long legs and long antennae is also a well-known form. Another one, which is a large, stout, dark-coloured ant {Ctmiponohis sp.) lives in the timbers, which it sometimes very materially weakens by its excavations. 147 In order to get rid of ants in the house, it will generally be necessary to locate the nest ; for unless the nest is destroyed, the egg-laying females continue their activities, and the supply of the individuals in the colony is maintained. The nest can generally be located by putting down a bait and watching to see the direction taken by the ants that have visited it. The nest may be destroyed in several ways, the method used depending somewhat on its location. Carbon bisulphide, cyanide of potash in solution, and hot water, are all useful for this purpose. Two or tliree oiuices of carbon bisulphide poured into the principal enti-ances of the nest will evaporate and produce i)oisoiious fumes which have great power of penetrating the galleries and killing the ants, both young and adult. In using this, entrances and exits should be plugged, to prevent escape of the fumes. Cyanide of potash in a 2-per cent, solution is used in the same way. The poisonous fumes are given off more slowly; but if the openings leading to the underground portions are thoroughly stopped, the ants will all be killed. Cyanide of potash is very poisonous, and must be used with great care ; it should not be entrusted to servants. In using hot water for this purpose, the fact must be borne in mind that it rapidly cools on coming into contact with the ground, and that in order to produce any great- ly increased temperature in an ants' nest at a depth of 0 or 8 inches, a liberal supply must be used. Most species of ants seem to have an extreme dislike for corrosive sublimate. Safes, larders and tables may be protected from invasion by washing with a solution con- taining corrosive sublimate, or in the case of those which SAving from above, by soaking a portion of the rope by which they are hung with this poison. Ants will generally not cross a siirface that has been treated with corrosive sublimate in this manner. The book solution, which has already been mentioned (p. 145), is useful for this purpose. The practice of standing the legs of a table or safe in vessels containing water and kerosene is well known to all residents in the tropics, as is also the use of a device which accomplishes the same purpose in connexion with hang- ing safes and larders. This is made by using an arrange- ment like an inverted cone to hold the oil and water ; 148 through the apex of the cone an iron hook passes, which attaches to the rope above and the larder below in such a manner that when this is in place ants which attempt to reach the interior of the larder by travelling down the rope by which it is hung find their progress imj^eded by the Avater and oil contained in the cone, (Fig. 156.) Ants may be collected and killed by the use of a sponge which has been dipped in a sugar and water mix- ture, or the hoofs of cows, called cow heels, or any bone such as chicken, beef, or mutton bones. These may be Fig 156. Hook for hanging safe. {Original.) put down where ants are abundant, and when they are covered with the insects, dropped into boiling water. If this is repeated frequently for two or three days, a sufficient number of ants will be killed to afford relief from their ravages. Some si^ecies of ants apparently leave the nest and establish anew one when they find their numbers rapid- ly diminishing. It must be bornC; in mind, however, that ants are not always attracted to the same food or bait, some species being very fond of sugar and starchy substances, while others are fond of meat, and if one form of bait is not found effective it is necessary to try another. 149 WHITE ANTS. Platyptcra. The Termites or so-called white ants (Fig. 157), or wood ants, are not true ants, but get their name from the similarity of their social organizations to those of the true ants in the order Hymenoptera. In their structure and life-history they more nearly resemble such insects as the pond-flies and the lace-wing flies. They live in large colonies which generally have an extensive central nest containing one or more fertile egg-laying queens, and enormous numbers of workers. These queens attain a size much larger than any of the workers, because of the Fig. 157. White ant. (a) neirlv hatched larra ; (b) same from be(o»r ; (r) egg, mvch enlarged. (From U.S. Dept. Agrir.) enormous distention of the abdomen which results from the development of the organs connected with egg-laying. (Fig. 158.) These insects are nearly always blind, and they hide from the light. When it is necessary to cross an exposed surface, they build tunnels or covered galleries, through which they travel from place to place. They feed upon wood, and are able to excavate timbers and lumber used in construction, to such an extent as to render them entirely worthless. They often attack picture frames, chairs, tables and other furniture, especially in old houses where these articles come into contact with the walls, or where they are not often moved, 150 Fig. 158. White ant. {a)qupen ; (b) nymph of luinqed fcmnle ; (c) worker; (d) All enhmjecf. (From U. S. Dept. Jiiric) >ldier. Wood ants are very difficult to control, when they have become established in or about buildings. The nests can sometimes be located, and if these can be thoroughly destroyed the numbers of the ants can be greatly reduced. These nests are often to be seen as irregular woody masses on the trunks of trees, and where they are thus found they may be cut down and removed. Domestic fowls and turkeys are very fond of these insects, and will eagerly eat them if the nests are broken up so that they are exposed. Sometimes, however, no nest can be found ; but if any of their galleries can be located, many of the ants Qan be killed by means of poisons. A mixture of arsenio 151 Fig. 159. White ant. a) adult male ; id) sfiiuc side vine ; b, a. d, e. atid f. struct urnl details, a, d and e enlarged ; b c, and f, greatly enlarged. (From U. S. Dept. Agric.) and sugar or strychnine and sugar can be put down in these galleries as a poison bait. The insects which are killed by this are eaten by other insects in the nest and the poison becomes widely distributed. A mixture of oak or spruce sawdust and either of the poisons mentioned may also be used as a bait. If a small box containing this ^flixture is placed in a building where wood ants ar^ 152 koowu to occur, and is kept slightly moist they will probably find it and will feed upon it. Sawdust or sheep manure in boxes, barrels or bags, left standing on the groiuid for some time, is attacked by wood ants. This fact suggests the possibility of successfully using poison baits in this manner. THE CLOTHES MOTHS, {Tinea spp.). Lepidoi)tera. Articles of clothing, especially woollens, furs, and feathers, Avhen stored for any length of time, are liable to be attacked by the caterpillars of these small moths, and housekeepei-s are generally familiar with the results of these attacks. When; such articles of clothing are taken out of trunks and packing cases, very minute moths are often se(^n flyiug about, and examination reveals the presence of many of the larvae. All such aTticles of clothing should he thoroughly aired and brushed at least twice a year. The boxes in which they are packed should be carefully lined with paper, special care being taken that there are no cracks or holes in this. The free use of naphthalene crystals or moth balls, in the boxes, will generally prevent the entrance of the moths. Small articles may be enclosed in tight bags made of paper or cotton, since these insects will not eat through cotton, even for the sake of reaching the more attractive contents. Fumigation with carbon bisulphide is also useful for their control. THE CIGARETTE BEETLE {Lasiodermci serricorne. Fab.). Coleoptera. This insect attacks a great variety of^'stored food stuffs but is probably best known in the West Indies as a household pest from its injury to books, cardboard boxes, photograph frames and similar articles, although it has a wide range of food materials, similar to that of theMrug store beetle. Books standing on shelves will often be found with holes bored through the covei's, and even through the entire thickness of the book. When such a book is opened, irregular tunnels through the cardboard of the cover, especially at the back near the binding, may often be seeo, and search will generally reveal one or more small whitish grubs, These are the larvae of the 153 cigarette beetle. The adult is a small, brownish beetle (Fig. 160) about ,V.-inc'h in length. Tody, with a short thick snout and prominent antennae. They belong to the 158 genus Bruchus, of Avhich there are several species, very much resembhng each other in appearance, in habit, and in the plants tliey attack. They are small insects, usually greyish in colour, with dai'ker markings. The larvae are short, thick, almost legless giMibs, which live and complete their development within the seeds of beans and peas (Figs. 166 and 167). Fig. i66. Cov/ pea weevil. Enlarged. {From, U. S. Dp.pt. Agric.) Fig. 167 Four-spotted bean weevil. (a) beetle; (b) larva ; (<■) pupa. All enlarged. (From U. S. Dept. Agrie.) The female j^arent deposits eggs on, or in, the seed vessel (pod) of the food plant, and the young larvae penetrate into the developing seed. These insects often cause much injury to stored peas, beans and the like, which are intended for planting, by destroying the germinating power. The adults emerge later through a round hole in each seed that has been attacked. Control. For the control of the pea and bean weevil, certain rules should be observed. It should be one rule to plant only uninfested seed, and another to destroy as far as possible the breeding places of the weevils during the time between crops of their food plants. When it is known or suspected that these insects have been abundant during the ripening of the crop in the field, the seed should be fumigated with carbon bisulphide soon after being harvested. The last pests in this division, to be considered, are the lipe fruit Hies, which are often seen on and about ripe fruit as numbers of very small insects. If these are examined, they will seem to be very handsome : the body a pale yellow, 159 the win^s a cloar lioiiev yellow, and the eyes reddish with opalescent chaiifres. There are many s]jecies of these in the West Indies, helonghig to the gemis Di'osophila. The parent fly deposits e<;gs in ripe fruit, where the larvae very rapidly develop. The life-cryole of these insects is extieniely short, only ahout ten days hein^- n'(|nired for the completion of the entire devi'lo])nK'nt, from the laying of the eggs to the a})])earance of the adult insec-ts. I^'ig. I(j8 shows Drosophila (niipclopJiila, Loew., which is very common in the I'nited States. Fig. i68. Ripe fruit fly. (a) ndnlt ; {b) anteiuia of same ; (c) basr offihia and first tarsal joint of same; {(1) j)uparium, side view ; {c) puparium, fr-om above ; (f)fullgrown larva; (g) oval spiracles of same. Enlarged. {From U. S. Dejit. Agric.) The most satisfactory method of controlling these flies is to remove over-ripe fruit, and to protect all other fruit by means of a fine muslin. Fruit on the table may be protected by a special dish cover, made by stretching muslin on a suitable frame, and larders may be equipped with a compartment enclosed in muslin, in which to keep fruit. 160 CHAPTER IX. The Control of Insects In the preceding pages, insect pests have been con- sidered in four general groups : the insect pests of crops, the insects which attack man, insect pests of domestic animals, and household insects, including those which attack stored products. In the matter of control, the same principles apply to all these groups, and control measures fall under two heads : one preventive, the other remedial. In dealing with insects of all kinds, preventive meas- ures are those which aim at debarring insects, by the destruction of their breeding places and of their food supplies, from developing to troublesome numbers, especially during the breeding season. Remedial measures are those by means of which the insects are destroyed after they become numerous. The use of insecticides comes under this head. Preventive Measures. General. Preventive measures are prophylactic and sanitary. In the case of field crops the methods employed include rotation of crops, resting or fallowing the land, the destruction of old plants after the crop is reaped, and of all dead and rotten portions of plants which are likely to furnish breeding places for pests. The clearing away of wild plants in which pests of crops develop is a part of the clean cultivation which comes under this head. These dead and worthless parts of plants should be burned or disposed of in such a way that all insects con- tained in them will be destroyed. Sugar-cane stumps often enable enormous numbers of weevil borers to breed to maturity. Old cotton plants furnish breeding places and food to scale insects, leaf -blister mite and other pests. 161 Insects ill the soil are able to live with very little or no food over the short interval which often ensues between two crops, and Avhen these are of the same or nearly the same kinds the increase in the pests may be enormous. If, however, a crop wliich is entirely xnisuited to tlie pests is planted between two similar crops, they are starved out. Ploughing, forking and hoeing are useful agricultural practices as preventive measures, because they expose a large number of insects to attacks of natural enemies. Cultivations of tree crops should receive the same con- sideration in the application of preventive measures as field crops. Pruninos and dead wood of all kinds should be gathered and burned, or buried dee})ly enougli to prevent the emergence of any insects which they may contain, and also to prevent adidt insects from gaining access to them for the purpose of egg-laying. In dealing with the pests which attack man, the great- est importance attaches to preventive measures. Mosouitoes breed in stagnant water which may be accvmiidated in swamps, ponds, pools, old tins, bottles, etc., in cisterns and watei- tanks, and even in hollows in plants, or in the sheath- ing bases of leaves of such plants as the wild pines. The removal of these breeding j^laces, or the treatment of them to make them unsuitable for the purpose, and the destruction of the moscjuito larvae by the use of kerosene, will have the eftect of preventing mosquitoes from becoming numerous. Cisterns and tanks may be enclosed with wire mesh, and they may be stocked with the fish known as millions. Millions are also useful in ponds and swampy situations. House-flies may be kept in check by the proper treat- ment of manure and all decaying organic matter which would furnish a breeding place for these pests. The occur- rence of fleas and bed-bugs in numbers can be prevented by the adoption of the necessary precautions and cleanliness. With regard to the occurrence of the insect and mite pests of domestic animals, the same rules in reference to pre- cautions and cleanliness hold good. Household pests may also be controlled to a large extent by similar means All food materials should be kept from these insects, as far as possible ; repellent substances should be freely used, and the utmost regard paid to cleanliness. 162 LEGISLATION AND IMPORTED PLANTS. Many inseots which have developed into pests of first importance have (lone so in countries or localities into which the\^ have been introduced. The admission of such pests has generally been in connexion with imported plants. The insects most liable to be brought in by this means are probably scale insects and white fiy ; but many others have been known to be intro- duced in this way. Insects which live as borers, or within the tissues of plants in any way, may easily be trans- ported and become established under new conditions. Grain and seeds also easily harbour insects, and provide for their introduction to new localities. In order to provide against the introduction of insect pests in this way, legislation has been enacted in all the West Indian islands, making it possible for the Governor of each Colony to pr.^scribe the conditions under which plant material of all kinds intended for propagation may be imported. The total prohi- })ition of the importation of all such plant material from any country where diseases and pests are known to occur, which it may be deemed impossible to flestroj' on imported plants, may be ordered ; while it is provided that all plant material intended for propagation shall be disinfected in such manner as the officer responsible for this work shall decide to be the most suitable. Fumigation with hydrocyanic acid gas and carbon bisulphide, and disinfection by means of Bordeaux mixture, are the methods most frequently prescribed. In Barbados, cotton seed imported for the manufacture of cotton seed oil is fumigated with sulphur dioxide. Remedial Measures. INSECTICIDES. These may be divided into four general groups : stomach poisons, contact poisons, fumigants and repellents. Stomach poisons are those substances which are used in such a manner tliat they will be eaten by the insect, and taken into the digestive system. It will be seen that such poisons are useful only in the cr.se of insects which bite off', and swallow, particles of food to which jDoison may be applied or of those which, having sucking mouth parts, will take an artificial food t(j whic'i a stomach poison has been added. 163 Contact poisons are useful against all soft-bodied insects which can he reached hy an application of substances that ma}' come into (tontact with their Wodics. It is obvious that insects which feed by puncturing the tissues of plants and sucking food from the juices within cannot be killed by the application of a stomach poison on the surface of tlie plant. Contact poisons are especially valuable in dealing with insects having this habit of feeding. Soft-bodied insects, such as some caterpillars and slugs, may also be killed by contact poisons, when this method is more (;onvenient than the use of the stomach poisons. Fumigants are useful for dealing with insects which cainiot be reached l)y stomach poisons or contact poisons, or live under such coiuHtions that it is jjossible to surround tiiem with a poisonous vapour. Insects of vai-ious feeding habits may be controlled by the use of this kind of insecti- cide. Repellents are often useful in situations where the other insecticides are not applicable, or in dealing with insects which are with difficulty reached by the other kinds of insecticides. As a preliminary to the consideration of the substan- ces used for the destruction of insects, it may be useful to review the structure of the mouth parts of tiiese animals and the manner in which they obtain their food. In general, it inay be said that insects possess mouth parts adapted for sucking or for biting. The jaws of insects are placed at the sides of the mouth and have a lateral motion. Strong mandibles are provided for the purpose of biting off' particles of food, while the max- illae aid in chewing and in conveying it to the gullet. Tiiis is the normal condition, which is found in such insects as the cockroach, grasshopper, beetles, both larva and adult, and the caterpillars of butterffies and moths. Insects which obtain their food by sucking it up in a fluid form possess mouth parts which are modified for the purpose. The mandibles or the maxillae, or both, are arrang- ed so as to form some kind of proboscis in which is combined the ability to pierce the tissues of plants or animals and to suck up the juices which are reached in this way. Mouth parts of this description are to be found in plant bugs, aphids, scale insects and wdiite fly attacking plants; and in ticks, lice, ffeas and bed-bugs, which attack animals. 164 Flies and bees combine an ability for biting and for lapping or sucking in the same individual ; while butterflies and moths are often able to suck up the sweet juices exposed in the nectaries of flowers, without possessing the ability to pierce any but delicate tissues. Thrips have remarkable mouth parts, in that one of the mandibles is well developed, while the other is much reduced in size. The well-developed mandible is probably used for cutting or lacerating the surface of plant tissue ; while the modified maxillae form a lapping organ, by means of which the soft tissues underlying the surface may be utilized for food. The larvae of the lace-wing flies have biting mouth parts, but modified in a peculiar manner. The mandibles are well developed, and grooved. The small insects on which these larvae feed are captured and held by the mandibles, while the body juices are sucked out by means of the grooves. As far as the structure of the mouth parts has relation to the use of insecticides, it is sufficient to classify them as biting and sucking mouth parts. A knowledge of the great modifications which have been brought about by the adaptation to different foods and different modes of life, will perhaps help readers of this book to realize the necessity of exercising some thought in preparing to deal with insect pests. STOMACH POISONS. The principal stomach poisons are those derived from mineral sources, and chief of these are arsenic and its several compounds. The arsenical insecti- cides are useful in combating nearly all insects with biting mouth parts, and may be applied to a great variety of plants. Leguminous plants (peas, beans, etc.) and the Cucurbitaceae (melon, cucumbers, etc.) often suffer severe injury when sprayed or dusted with this class of poison, and trials should be made on a small scale before treat- ing large areas uf these crops, iu order to determine the correct strength of the application under the existing local conditions. Paris green. Paris green depends largely for its effectiveness on the amount of arsenic which it contains, the arsenic being united with copper which is also com- bined with acetic acid. A good quality of Paris green should contain not less than .")(! \)vv cent, of arsenic, of which only about 5 per cent, should be soluble in water. 165 The soluble arsenic in Paris green, or in any arsenical insecticide, is liable to injure the foliage of the plants to which it is applied : and it has l)een found that when the percentage of this is more than the i)ro])()rtion already mentioned considerable injury to plants is likely to result. Paris green may be used either as a spray in a mix- ture with water, or dry. When applied dry it may be employed by itself or mixed with lime or any other dry fine powder. If it is used as a spray, the Paris green mixture should be applied by means of a very fine no/.zle attached to a fairly strong force pump. When used dry, it should be very evenly distributed over the surface of the plant in such a way that all parts are reached by it, and at the same time, so that there is no thick layer of this substance on any part of the plant. It has l)een found in practice, in the West Indies, that Paris green is best applied as a dry mixture with finely pulverized air-slaked lime, the mixture bein^; at the rate of 1 lb. oi Paris green to 5 or (i lb. of lime. The same proportion will l)e maintained if the mixture is made by using one part in bulk of Paris tureen to ten or twelve parts of dry air-slaked lime. Several mechanical devices are available for the applica- tion of dry Paris green, some of which will be found under the heading of The Application of Insecticides. For use in cotton fields, and in connexion with similar low-gi'owing crops in the West Indies, it has been found that cloth bags of fairly fine mesh are ver}' satisfactory for the distribution of Paris green. Paris green is useful in coml^ating a great variety of insects which have biting mouth parts. It has l)een most used in the West Indies in deahng witli the cotton worm ; but in other parts of the world it has been employed against nearly all kinds of leaf-eating caterpillars, grasshop- pers and cut worms. Paris green is used as follows : — As a spray. 1 Bb. to 150 to 200 gallons of water. Mix the Paris green to a paste in a small amount of water before making up to the full quantity. Add 2 lb. of freshly slaked lime to each pound of Paris green. Apply by means of a force pump, using a nozzle which gives a very fine spray. As a dust or powder. Mix Paris green and dry air- slaked lime in the proportion of 1 ttj. of the former to 5 or fi 8). 1G6 of the latter. Apply by means of a powder gun, bellows or cloth bag, in such a way that the mixture shall be evenly distributed over the plants to be treated. London 'puvpJe. London purple is also an ai-senical stomach poison, and is a compound oi arsenic and lime, con- taining a certain amount of colouring matter. The percent- age of arsenic is smaller than that in Paris green, while a larger proportion of the arsenic present is likely to be soluble. It will be seen from this, that while London purple may be used in a manner exactly similar to that for Paris green, it ought always to be cheaper than this insecticide. It should be remembered, also, that the greater solubility of the arsenic in London purple requires that it should be used more carefullv than Paris green, on account of the greater danger of injuring the foliage of plants. The directions for using Pans green apply to London purple, both in the form of a spray and a dust. Arsenate of lead. This is also an arsenical stomach poison. It is usually sold as a paste, and in this form can only be used as a spray in a mixture with \\'ater. Recently however, it has been put in the market in the form of a powder which, it is stated, can be used in the same manner as dry Paris green or London purple. The advantage attending the use of arsenate of lead results from its great degree of insolubility, and consequently the large comparative safety attending its application to plants A disadvantage w^iich has been experienced in the West Indies results from its slower action as a poison. On this account, it has not been received as favourably by planters as Paris Green and London purple. When used as a spray, 2 or 3 lb. of arsenate of lead in 50 gallons of water will be found satisfactory for the iiiontrol of most caterpillars. The strength of the mixture may be increased, however, with very little danger of injuring the foliage of the plants. The dry form of arsenate of lead ma}^ be used wdthout being mixed with lime, as on account of its white colour it can easily be seen on plants treated. White arsenic. This is a stomach poison, but it is not adapted to general use. Its greater degree of solubility malces it less satisfactory to apply to the foliage of plants, since on account of the possession of this property it is liable to cause burning or scorching. 167 This poison Huds its pi-iiu-ipal us,' as an insi'c-t icidc in the preparation of poison baits for such insects as <^rass- hoppers, termites, cut worms, beetle grubs and crickets. For use against cut worms, as a poison bait, mix 1 lt>. arsenic with 25 tb. bran or pollard, and stir to a thick mash with water to Avhich molasses or sugtxr has been added to impart a sweet taste. A tablespooni'iil in each hole at the time of planting cotton or other seed will !)■' found sufHoient to kill pracitically all the cut worms. For use against grasshoppers, takf.; halt'-l) irrel of fresh (or moist) horse drop])ings. 1 lb. salt and 1 ll». arsenic, and thoroughly mix. Paris green or London purple may be used instead of the arsenic. This mixture, put down freely in small heaps containing a half-pint or less, in any field or infested pasture, should give good results. For use against termites, when these appear in buildings, a mixture of arsenic and sugar in the proportion of one of arsenic to two or three of sugar will be found useful in checking the increase of these pests. The covered gallery of these insects should be broken away for an inch or two, and the poison put down on the broken portions. The poison will be eaten by a few ants, and these by others, so that a small amount of poison thus applied will be dis- tri))uted through the nest or colony. Arsenic also has an action as a contact poison aiul forms one of the constituents of certain cattle dips and washes for the destruction of ticks. Corrusive sublimate. This is a very powerful poison and it is not used for general insecticidal purposes. It has a very injurious effect on the foliage of plants, and its extremely poisonous nature makes it a dangerous substance to put into the hands of ordinary labourers. It is useful for the purposes of disinfection, since it has a fungicidal action. It is employed in the preparation of book solution, which is used to protect the bindings of books from the feeding of cockroaches, silver-fish and to some extent from that of the book worms, which are the larvae of the cigarette or the drug store beetle. Book solution is composed of the following materials : — Corrosive sublimate 1 oz Carbolic acid 1 oz. Methylated spirits 1 (juart This mixture, applied to the l)inding of bo:)ks by means of a tine brush, is an excellent protection. The carbolic 168 acid and the corrosive sublimate are, on the evaporation of the spirit, left as a very tine covering of poison on the entire treated surface. The poisoning has to be repeated from time to time, according to climate and the abundance of insects. Books thus treated are quite safe to haiidle. Corrosive sublimate, used for disinfecting seed for planting, protects it from subsequent insect attack by means of the fine deposit of poison on the surface of each seed. Corrosive sublimate also has a strong effect as a repel- lent for ants. The legs of a table or safe washed with any solution or mixture of this j^oison are quite safe from attacks as long as the poison remains. Ants apparently will not cross any surface treated with corrosive sublimate. Boric or boracic acid. This is a specific as an insecti- cide for cockroaches. Although not a poison in the ordinaiy way, this sul)stance seems to have a particularly deadly effect on these insects, and it is of course especially valu- able for use in dwelling houses, since cats, dogs, fowls and even human beings are not injuriously affected by it if it should be eaten by them. Equal parts of boracic acid and sweet chocolate, Hour, molasses or sugar, put down in places frequented b}^ cock- roaches, will be effective in reducing their numbers. When one mixture has been used for a short time, a change to another of those suggested will be found of advantage. Phosphorus. This substance is often used in the pre- paration of rat poison and in poison, for crabs. Rat poison containing phosphorus is eaten to some extent by cockroach- es, apparently with effect. The insecticides mentioued already ai^e mineral poisons. Several vegetable siibstances are useful as insecticides, the chief of which are pyrethrum, tobacco and hellebore. Vege- table insecticides lose their power when exposed to the air for any time, and on account of this tendency, are likely to deteriorate in the tropics. Pyrethium is composed of the finely ground dried flower heads of a plant of the Chrysan- themum group Pyrethrutn roseiim. Pyrethrum, Dalma- tian and Persian insect powder, and Buhaeh are names given to this, and to other products from closely related plants. 169 Pyretlimun. This is a very useful insecticide, possess- ing ([ualities both as a stomach and a contact poison. When fresh and of full strength it is a bright yellowish powdei' with a pungent ordour, rather i)leasant than otherwise. In the tropics it fiuds its greatest usefulness in connexion with Heas, lice and bed-bugs. Applied dry to the coats of dogs and c^ats, and to the plumage of fowls, it very quickly drives out Heas and lice, killing many of them. Travellers in the tropics would do well always to carry a supply of pyrethrum. A little scattered between the sheets in hotel beds may ensure a good night's rest, which otherwise might be impossible. For use on iiouse plants pyrethrum is of great value. An oiuice of this substance l)laced in one quart of hot water and then diluted to make one gallon, forms an excellent spray or wash for killing caterpillars and other small soft- bodied insects. A mixture of jjyrethrum with twice its bulk of flour makes an excellent insecticide, the flour absorbing a certain porportion of the poisonous quality, and all parts of the mixture becoming equally effective. Pyrethrum, Ijurned in a room which can be closed will stupify all mosquitoes and flies, and they can be swept up from the floor and destroyed ; if left to them, selves, however, they will recover. For this purpose 8 Iti to each 1,000 cubic feet is the amount to be used. Tobacco. Tobacco has a wide range of usefulness as an insecticide, and when the stems, broken leaves, dust, etc. are easily obtainable they may be put to a variety of uses both as a contact insecticide and as a repellent. At the present time, there are several excellent pre- parations on the market which are prepared from tobacco, but these are probably not to be obtained in the West Indies, Tobacco dust, api)lied dry, has much the same uses as pyrethrum, and in a decoction also it is useful in the same way, while it is even more so as an application to the soil for the destruction of grubs, worms, and small pests about the roots of plants. Tobacco dust and stems applied to the surface of the soil about cabbage, melons, cucumbers and many ornamental plants will often serve to keep ofl' injurious pests. Tobacco stems are useful in the nests of sitting or laying hens, as a remedy for poultry lice. 170 Hellebore. Hellebore consists of the finely ground roots of Veratrum album, a plant of the order Liliaceae. It is used in temperate climates for the control of soft-bodied slugs and caterpillars, on certain plants, but will prol)ably have only a limited application in the tropics. Its proper- ties are similar to those of the vegetable poisons already mentioned, but it is not as stroi:g in its effect. CONTACT POISONS. Contact poisons are generally more difficult in preparation for use than the majority of stomach poisons, since most of them are mixtui^es of several sub- stances, which require care in their jDreparation. The effect of contact insecticides is to cause the death of insects by clogging or closing the breathing openings, (stigmata), by penetrating the stigmata and breathing tubes and thus causing a fatal in-itation, or by forming a thin coating on the entire insect and sealing it down to the leaf or bark on which it occurs. It Avill easily be seen, then, that for these to be effective, the insecticide must be brought into contact with the insect, careful application of the spra}^, wash oi- dust being most essential to successful results. The materials which are most likely to be found useful as contact insecticides, either alone or in combination, are the following : whale-oil soap, tish oil, rosin, soda, soap, kerosene, sulphur, and lime ; while pyrethrum, tobacco, hellebore, turpentine and hot water are all to be included among the insecticides of this group. Whale-oil SoajJ. This is a ver}^ useful insecticide, especially for plant lice, leaf-hoppers, thrips, mealy-bug, white Hy, and certain scale insects. It is also useful for treating insects at the base of plants, in pots or garden beds, and it may be used with good results on caterpillars and other soft-bodied insects which feed in exposed situations. It has the advantage of being easily prepared for use, and the disadvantage, or what is considered to be so l;)y man}', of being very foul-smelling. It is used in solution, in varying strengths. Palms and other plants with tough leaves will suffer no injur^' from the application of the stronger mixtures, while for tender-leaved plants the strength may be much reduced. Whale-oil soap is prepared for use by mei'.ely being dissolved in water, the proportions being from 1 ft. in 2 gallons to 1 BE), in 8 gallons, of water. 171 lio.si)!. Tlie Hprav inixtun-s containing; i-osin are useful in conibatinj^ the nnannoured scales (Saissetia, Coccus), and other scale inset;ts and thrips ; but is of most value in dry seasons and when the young scales are most abundant. Rosin is applied in combination with other materials as a spray or wash. Rosin compound is made of : — Po'A'dered rosin 4 tt>. Powdered washing soda 3 &. This quantity is sulHcient to make 30 gallons of wash. It is prepared by mixing the constituents thoroughly, and dissolving by boiling, in 1 gallon of water, in a vessel with a capacity of at least 5 gallons. Water is slowly added to make 5 gallons, the mixture being kept boiling. This is the stock solution ; when cold it should be of a clear brown colour. For use. add 5 parts of water to 1 of the stock sohition. Rosin wash is similar to the preceding, but contains an oil, which gives it a more penetrating effect. Rosin wash is thus constituted : — Powdered rosin 20 lb. Caustic soda 3| lb., powdered tine. Fish oil 3 pints, which will be suffici- ent to make lOU gallons of wash. Mix these materials, and cover with about 2 inches of water, and boil. When the liquid is clear, add water slowly, still boiling the mixture, until the whole is made up to 15 gallons. This is the stock solution, sufficient to make 100 gallons of wash. In diluting this, only rain-water or soft water should be used. Ro8i)i and Whale-oil Soap Compound. This is a still more general insecticide. It consists of : — Powdered washing soda 3 lb. Powdered rosin 4 ft. Whale-oil soap 10 ft. To obtain it, boil the soda and rosin in 1 gallon of water until they are dissolved, then make \\\) slowly to 5 gallons, still boiling the mixture. In another vessel, dissolve 10 ft. of wdiale-oil soap in 5 gallons of water, by boiling. The stock solution is made by mixing these two solutions. This is sufficient to provide 45 gallons of wash. 172 Keronene Enmlsion. This is one of tlie most useful of all the contact insecticides, for sprayino; plants against scale insects, mealy-buo and all related insects. The difficulty of getting a true emulsion with the water which is available in many localities has proved an objection to its use, but with care and by the use of rain-water, an emulsion ought to be obtained. Kerosene emulsion is made from : — Hard soap -|-5). Kerosene 2 gallons Dissolve the soap in 1 gallon of water, by boiling. Remove from the fire and immediately add 2 gallons of kerosene, and churn violently wdth a syringe or force pump until the mixture becomes creamy, and the oil is all held by the soap. This is the stock solution, and is sufficient for 33 gallons of wash. Great care should be taken to get a perfect emulsion, as any free oil is likely to injure the plants. If any considerable layer of oil is observed on the surface of the stock solution when it has stood for 24 hours or more, the emulsion is not perfect. If difficulty is experienced in this respect, an increase of the amount of soap will often aid in producing the emulsion. Kerosene Emulsion, ivith soft soap. This is similar to the preceding both in its action and in its use. It is made from : — Soft soap 1 quart Kerosene 1 pint To prepare it, dissolve the soap in two quarts of hot "vrater and add the kerosene, making the emulsion in the manner described above. This is the stock solution and is made ready for use by adding an equal amount of water. Kerosene. In addition to its application in kerosene emulsion, this oil may be made to form a valuable insecticide in other ways. It may be used in a mechanical mixture with water, by means of a special pump, as a spray for scale and other insects, and when used by itself produces excellent results in special cases. Mosquito larvae, in tanks, water barrels, and similar situations where it is not desirable to introduce fish, may be destroyed by an application of kerosene to the surface of the water. The larvae are killed by the kerosene when they come to the surface to breathe, the oil penetrating the breathing spiracle and causing death. - 173 Honseholfl insects siioli as ))Ofl-l)ngs, ants in floors and termites in woodwork may be destroyefl l)y the free nse of kerosene, and many living insects wliicli are attracted may 1)6 eaugiit in a travof water and kerosene over which a lio-ht is^snspended. The insects, ilyin*^ to the ligiit, fall into the tray below, where they are killed l)y the lilm of kerosene on the watei". Tobacco and Soap. Tobacco and soap is often a conve- nient mixtnre, especially for honse plants, where the smell of whale-oil soap would be an objection to employing that substance. It is composed of : — Soft soap 1 quart or Hard soap ^-ft). Tobacco refuse i Bb. Dissolve the soap in 5 gallons of water, steep the tobacco in 2 quarts of water for 24 hours, strain and] add to the soaii solution. This mixture is used without fur- ther dilution. Crude Oil and Whale-oil Soaj}. This mixture has a wide range of application and jjossesses the valuable (luality of keeping well. It is sold in Barbados under the name of Lefroy's mixture, Mr. Lefroy being the originator of the compound. Whale-oil soap 10 lb. Crude Barbados oil 6h pints Nai)hthalene 4 oz. Heat the soap in a metal vessel. Dissolve the naphtha- lene in the oil by stirring. Add this mixture to the hot soap, away from the fire, and thoroughly mix the whole by stirring. A nearly solid soap-like substance is produc- ed which is prepared for use by rubbing up or stii-ring it in water. Use at the rate of 1 It), to 3 lb. in 10 gallons of water. Sulphur. Sulphur may be used either dry or as a spray. When used dry, it may be applied by itself or in a mixture with varying amounts of lime. When used as a spray, 1 It), in from 2 to 4 galhms of water is a con-' venient strength. Sulphur lias a special value in combat- ing mites of all sorts, including ticks, poultry mites, red spider, leaf-blister mite and the orange rust mite. It is also a constituent of many ointments, applied in the ease of mange, itch and similar affections, which are due to the presence of mites. 174 When used for the control of ticks on animals, sul- phur is best combined with oils as is suggested on p. 131 Sulphur and lard well mixed and used on setting hens will prove effective in preventing the attacks of mites and lice. Sulphur and air-slaked lime, in equal parts, dusted on the leaves of plants controls plant-feeding mites, red spider and thrips. Sulphur dioxide, made by burning sulphur, is useful for fumigating buildings, holds of ships and similar places, for the destruction of mosfpiitoes and of insects in grain and seed ; but the tarnishing effect of the gas on metals re(|uires that care be exercised in using this substance in houses. Seeds for planting should not be fumigated with sulphur dioxide, as their germinating power is injured, and often in face completely destroyed, by this process. Carbon Bisulphide. This is one of the most useful insecticides for fumigating purposes, as it possesses a veiy wide range of application, and is very effective in the des- truction of insects. Carbon bisulphide is a liquid slightly heavier than water, which volatilizes rapidly at ordinary temperatures. Its fumes are much heavier than air, and have a very considerable power of penetration. They are inflammable and slightly poisonous to man, so that care must be exercised when this insecticide is being used. Carbon bisulphide can only be used successfully when the fumes can be confined in a receptacle which is practi- cally air-tight. It is especially valuable for the destruc- tion of insects attac;king stored products of all kinds, such as grain, flour, household stores and drugs, books, music, papers, clothing and all similar materials. Gran- aries, store-rooms and dwelling houses may also be fumi- gated for the destruction of insects, while it is effective for dealing with ants and grubs in the soil. Grain, seeds, flour, books and clothing can be treated in tight boxes, casks or hogsheads. The amount to be used is calculated in large enclosures at the rate of 1 It), per 1000 cubic feet of space ; for grain in bins, 1 It), per ICO bushels. For dealing with smaller capacities the amount to be used is 1 drachm, or roughly a teaspoonful, to each cubic foot of enclosed space. This can be easily calculated 175 for any rectangular box, and if the following doses be taken as coriect, barrels, casks and hoo;shf'a(ls may be used to tfood advantage. gating with carljou bisulphide in a Hogshead Cask or ])uneheou Barrel use 5 oz. of the li(]uid ., 2 oz. ,. „ ., 1 oz. „ „ „ In using earlxju l)isulp]iide, it must be remembered that the fumes are ver^' iiiHammal)le, and no fire, pipe, cigar or other light should be brought near on account of the danger of an explosion. The fumes are also heavier than air, and conseciueiitly, tlie liipiid to be evaporated should be exposed, in a shallow (hsh, at the top of the room, box or other cfjutainer. The carbon bisulphide will evaporate, and the gas descend and penetrate through all the interstices. If a wooden box with a cover is used as a fumigating chamber, a hole in the cover, with a wad of absorbent cot- ton attached below, will provide for the introduction and evaporation of the insecticide, the hole being closed with a cork. A blanket or tarpaulin serves well for a cover to a barrel or hogshead, and a saucer or similar dish will answer the purpose of a receptacle and evaporator. The evil smell of this insecticide will quickly disappear when the fumigated articles are exposed to a free circula- tion of air. Ants in lawns or in garden l)eds may be killed by the use of carbon bisulphide, b}' merely pouring into the principal entrance to the nest 2 or 3 oz. of the liquid, and closing it with soil. All other entrances and exits should be closed, and the fumes penetrating to the deepest recesses and through all the galleries will completely kill out the nest Nematodes and grubs m ly be treated in a similar manner. Carbon Ijisulphide has a limited application as a garden insecticide for the destruction of plant lice and similar insects on low-growing plants. A box of 2 or 3 cubic feet capacity makes a convenient fumigating chamber when placed over an infested plant. A hole in the top of the box will serve for the introduction of the insecticide, while a wad of absorbent cotton on the inside of the box under the hole will serve as a receptacle and evaporator. The hole can be plugged with a cork. 176 Cyanide of Potash or Potassium Cyanide. Tliis insecti- cide can be obtained by mixing potasli with prnssic acid. It is an extremely poisonous substance, wliicli has in i^ecent years come into great prominence in connexion with the fumigation of Hving plants infested with scale insects In many parts of the world fruit trees are fumigated regularly for the control of insect pests, the trees being covered for the purpose by means of tents of air-tight canvas to confine the gas made fi'om the potassium cyanide in proximity to the parts of the tree. In the West Indies, fumigation of trees has not become a regular practice, chiefly on account of the expense of the process, which is very large in proportion to the value of the products of the trees. Imported plants are fumigated, according to law, before l>eing allowed entry to any colony for the prevention of the introduction of insect pests. In using potassium cyanide for fumigating piu^poses, hydrocyanic acid gas is produced by the action of sulphuric acid and water on it, in the following proportions : — Potassium cyanide 1 oz. Sulphuric acid li oz. Water 2j oz. These amounts are suitable for an enclosed space of 300 cubic feet. Potassium cyanide can be used with good results for treating many of the insects for which carbon bisulphide has been suggested. The verj' poisonous natui^e of this insecticide must be borne in mind, however, and only responsible persons allowed to handle it. It is probable that food stuffs would not be injured or rendered poisonous by being fumigated with potassium cyanide, but many persons would very likely prefer not to take the risk. Books, clothing, and grain, however, might safel}' he treated with this material, if this is desired. Ants may be killed by pouring into the nest a solu- tion made by disscjlving i-oz. of potassium cyanide in 2'quarts of water. The dissolved poison penetrates the soil, and gives off fumes which kill the insects. 177 Camphor. Camphor as a repellent, and to some extent as a fumigant, has a vahie as an insecticide. Placed in trunks, boxes and wardrobes, it has a tendency to keep out moths, cockroaches and similar insects. It is useful also for keeping the nests of fowls free from parasites. As a fumigant, caiojihor in ecpial parts with carbolic acid, is excellent for killing mos(iuitoes in the rooms of dwelling houses. Four ounces of this mixture for each 1.000 cubic feet of space in the room, vaporized by being placed over a gentle heat, will kill all the mosquitoes if the room is tightly closed for two hours. This is one of the best fumigants for this purpose : the fumes are prac- tically harmless, possess excellent disinfecting qualities, and leave in the room a pleasant, refreshing odour. Naphthalene. This is sold in the form of flakes and crystals, and in moth balls, and in both forms is well known for its characteristic odour which has the property of repelling insects. Used in the manner suggested for camphor for protecting clothing, books, etc., in boxes and trunks, it is both cheap and effective. A very strong atmosphere containing naphthalene is fatal to many insects. The flakes seem to be more effective than the moth balls, no doubt because the former volatilize more rapidly, and partly perhaps because they can be more thoroughly distributed throughout the materials to be ))rotected. Some persons object to the odour of naphthalene, but in many cases this is largely due to their not being sufficiently familiar with it, and at the same time their not realizing the ver}' considerable usefulness of this insecticide in the protec- tion it gives from tropical insects. Naphthalene is one of the constituent parts of Para- naph, an insecticide originated by the Jamaica Department of Agriculture, which is said to be of value as a contact poison for the destruction of fleas, ticks, plant lice, and cer- tain scale insects. Alum. Alum is said to repel or to destroy fleas when dusted on the floor of an infested room, and when used for that purpose, to prevent the occurrence in beds of these 178 insects and of lied-bugs. An old sheet soaked in a fairly strong solution of alum in water and then wrung out and dried, retains a sufficient amount of alum so that when it is spread over the mattress and under the sleeping sheet it keeps away these undesirable insects. Creasote and Carbolic Acid. These are satisfactory repellents when used for certain purposes. Creasote, applied to wood and timber, prevents the attacks of termites for a time, and carbolic acid, added to lime wash, is said to in- crease its efllectiveness when applied to the trunks of trees to prevent the entrance of boring insects. Mixed with lime at the rate of 1 pint of the crude acid to every 100 ft. of the lime, it forms a repellent which, dusted on the leaves of certain plants protects them from the attacks of insects. This method may be employed against weevils and certain other beetles wliich are not easily killed by Paris green. The best way to prepare this material is to slake to dryness tomper lime with water to which the carbolic acid has been added. Carbolic acid is also useful for treating wounds infested with screw worm, since it cleanses and disinfects them, and kills the inaggots. Air-slaLed Lime. This is sometimes employed as a repellent, with good results. When it is mixed with Paris green or other arsenical poisons, its effect is that of combining with the free arsenic and thus reducing the amovmtof burn- ing of the foliage ; it also indicates plainly where the poison has been applied. Aromatic Oils. Mosquitoes, gnats, sand Hies and similar insects, which annoy by their persistent attacks, may be kept away by smearing the hands and face with an aromatic oil. Citronella, lavender, bergamot and other oils are useful for this purpose. An excellent mosquito repellent may be made by mixing equal parts of sweet oil and oil of citronella. Turpentine. Turpentine has a limited application as an insecticide. Applied to infested beds it kills bed-bugs, in the egg, larval and adult stages. For treating screw worm in wounds, it is also of value and is applied by means of a brush or swab in such a manner that the breathing openings of the larvae will be touched by the||turpentine. 179 Price List of Insecticides r\ Barbados, 1911. Palis tureen ... per tt). 28-30 cents. Loiuloii purple ... ,. 21-30 „ Arsenate of lead ... ... „ 24 „ White arsenic ,, Cyanide of potash ... ... ., 72 ., Corrosive sublimate ... ., $ 1-44 „ Boracit^ acid ... ., 40 „ Phosphorus $ 1-44 „ Carbon bisulphide in 1 lb. tins ... „ 60 „ „ ,, Fuma brand in .5gal. drums „ 15 „ Whale-oil soap ... „ 10-12 „ Hard soap ... „ t) ., Soft soap ... ,. 12-18 „ Fish oil ... per gal. 48 60 „ Rosin ... per lb. .T ,, Washing soda ... „ 4 ., Caustic soda 24 „ „ ill 10 U. tins ... ... „ 18 „ Carbolic acid (cinKlc) ... „ 21 ., Lime, air slaked ... pel- b-.i.shel (5 ,. Sulphur (Howc'i-s ... ... per lt>. (5 ,, Pyrethruni 72 Hellebore '■■ I 34-48 !; Tin-pontine . per pint 18-21 „ Kero.sene ... per gallon 1-5 ,. Citronella (oil) .. peroz. 12 ,. Lavender (oil) 24 „ Bergamot- (oil) • • ., 21 „ Naphthalene, small quantities ... per lb. 24 „ „ in large quantities • ., 12 „ Camphor ... peroz 10 ,, Alum ... perltx 10 „ ,, in large quantities -.. „ 6 ,, THE APPLICATION OF INSECTICIDES. Within the past few years, great progress has been made in the development of pumps, nozzles and other appliances for spra3nng plants, and there are also many devices for the dry application of insecticides. Spraying apparatus ranges from elaborate power outfits to portable sprayers carried by one man, and syringes, atomizers and similar simple machines for the treatment of liouse and garden plants. 180 The essentials foi- spraying are tlie pump, the con- tainer, the hose and the uo/zle. The pump should be strong and durable, and is generally liest when the working parts are of brass. An agitator is also essential ; this is generally attached to the pump. Mo'^t of the spray mixtures that are used require to be constantly stirred in order that the spray shall be of uniform quality during the entire operation of spraying. The no/.zle is also of first importance. Its structure should bo such as to produce a very fine spray, thrown \\ ith force from the apei'ture, and an extension consisting of a suitable length of gas pipe should be used to connect the nozzle with the hose, in order that the distance between the nozzle and surfa(ie being sprayed may be very short. Fig. 169. Spray nozzle-. (l}Bordeaii.> ; (,'», {3)and {4)rari('fic.s of Vciiionl. Ur.land. {Original.) The Vermorel a fine spray. This nozzle is made form which produces such sevei-al different patterns, IS maae \\\ but the essential features are the same in all. The nozzles shown in Fig. 109, Nos. 2, 3, and 4 are patterns of this type. No. 4 being merely two nozzles fixed to a single feed pipe. Nozzles in groups of three or four are also manufactured. The Vermorel nozzle is especially suited for spraying SQlutions, and mixture^ containing no solid particles which 181 might cause clog^jjing. A plunger suiTOtiiulefl hv a spiral spring, shown in the illustration, is provided for clearing the nozzle if it becomes clogged. The Bordeaux nozzle (Fig. 1(51*, No. 1) is adapted f(»r spraying Bordeaux mixture and other spray Huids v/hich are not true solutions or that contain solid particles which would clog a nozzle like the Vermorel. The Boi- deaux nozzle is adjustable, being capable of thiowing a solid stream when it is necessary in oider to apply the insecticide at some distance from the nozzle, and also of throwing a fairly fine spray. In spraying for the control of scale .ind other sucking insects with soft bodies, the object to be aimed at is to get eveiy pait of the plant wet, but not sufficiently so to cause any drip]jing from the leaves or branches. Spraying with a stomach poison is for the i)urpose of applying the poison in such a way that, in order to obtain its food, the insect will have to eat the i)oison. The success of spraying depends on the care and intelligence with which the operation is conducted. Power Sprai/ers. These are not likely to be adopted for use in the West Indies, because of their very consider- Fig. 170. Fruitall sprayer. Side of barrel cut auuy to alwupnmp and agitator 182 able cost and large size ; the latter renders them unsuit- able for the large majority of estates, where the ground is rocky and uneven. Barrel Sprayers. These are cheap and very efficient. There are many good styles of barrel spray pumps on the market, a good idea of which may be obtained from the accompanying figures. These outfits may be mounted on Avheels, and in fairly le\el situations they can be handled easily. (F'igs. 170 and 171.) .^o I Fig. 171. Gem spraying outfit. Certain of these pumps will easily supply two lines of hose, with one man to work the pump, while others are capable of supplying only one line. The spraying gang will thus consist of either two or three men who move the outfit from place to jjlace. Knapsack Sprayei'S. The knapsack sprayers are more portable than the barrel sprayers, being adapted for use by one person to each outfit. The Success knapsack sprayer and other machines of the same kind consist of a tank with a capacity of about 5 gallons, with a small force pump attached. The outfit is carried slung on the back of the labourer, the spray fluid being discharged by the action of the pump. The operator works the pump and directs the spray. 183 Fig. 172. Success Knapsack sprayer and bucket pump. Another form of knapsack .^prayer is the Auto Spray which consists of a tank of about 5 gallons capacity, with a pump attached. TJie object of the pump is to force air 184 into the cylinder, which is air-tight. When a sufficient amount of pressure has been produced, the spray fluid is allowed to be forced out by the air pressure. In using this type of sprayer it is not necessary for the operator to pump and spray at the same time. Bucket Sprayers. These are small pumps which are adapted for use in a bucket or other small vessel. They are very useful in applying a spray to a small number of plants, in a garden or conservatory. Garden syringes and atomizers are hand sprayers adapted for treating small plants or a few of them. Their small cost and their adaptability to the requirements of persons having only a few plants to treat, make these instruments more popular than the more expensive ones, Many of them, however, get out of order easily if not used for a time, and others have the disadvantage of not throwing a fine spray. A sprayer of this genera! type that has given satis- faction in the West Indies, as far as it has been tried, is called the Abol syringe; it is equipped with a drippreven- Fig. 174. Abol syringe. Length sliglitly reduced. (Redmun from advertisement.) ter which- saves the operator from becoming wetted with the drip running back down the syringe, and is provided with a good nozzle, which produces a very satisfactory spray, very similar to that formed by the Vermorel nozzle. For the application of dry insecticides such as Paris green, lime and sulphur and similar substances, as a dust, the powder gun, the bellows, or the cloth bag are all of value for certain purposes, and such insecticides may also be applied direct from the hand in the manner of a sower sowing small seed broadcast. This last method should be generally employed in treating trees, such as the orange or lime, which are too tall to allow bags or a powder gun to be employed. -. - 185 In the West Indies, by far tlie greater part of the stomach poisons are applied in a dry condition. The powder j^iin has been used to a small extent, but on account of its cost and the number of working parts planters do not care to put it into the hands of irresponsi- ble labourers. In this form, the poison is contained in a receptacle, from which it is forced by an air-current generated by a revolving fan through a discharge tube, in a tine cloud of dust. The fan is operated by a wheel turned by the labourer. The powder bellows is an instrument of the ordinary bellows type ; in this is placed a suitable amount of insecticide, which is forced out as a cloud of dust by successive putts. An inverted funnel attached to the out- let serves to spread the discharge. (Fig. 175.) Fi&- 175- Acme powder bellows. The most generally employed method of distributing dry poisons in the West Indies is by means of the cloth bag. Ticklingburg bags, of a suitable size held in the hand of the labourer have given every satisfaction in distributing Paris green and London purple, for combating the cotton worm. The bags are cheap, they cannot get out of order, and a very even application of the poison mixture can be made with them, a slight shake of the hand producing a fine cloud of dust which settles down on the plant. Tin shakers, consisting of a tin vessel with a perforated bottom have also been used in the same manner as the cloth bags. These do not generally distribute the poison in such a tine condition, with the result that a larger amount of insecticide is used. 186 CHAPTER X. Insects and their Natural Enemies. Insects, in the present age, may be said to be the dominant animals of the world. Not only do they greatly exceed all other classes of the animal kingdom in point of numbers of species, but many of these species occur in most amazing abundance. Like all othei- living creatures, they form part of a complex scheme in nature made up of relationships between these forms. The relationsliip of insects to plants is generally that of an animal to its food ; that is to say, insects for the most j^art are plant feeders, and when this relationship exists between an insect which occurs in considerable numbers, and plants which are of use to man, the insect is generally considered a pest. Some insects also procure their food by sucking the blood, or devouring the tissues, of animals. These may be parasitic or predaceous. Other insects, still, derive their sustenance from dead or deca^dng organic substances, and are known as scavengers. Insects also serve as food for other insects, for birds, toads and lizards ; these are called their natural enemies, and there are also certain forms of plant life which are able to attack and kill living insects, which are also to be included among their natural enemies. It will thus be seen that insects play a considerable part in the relationships which exist in the plan of nature. If it were not for the effect of natural enemies on insects, the world would in a short time become absolutely uninhabitable to any other forms of life, except perhaps the very lowest plants and animals, and the insects themselves would shortly die off, killed by starvation. The natural enemies of insects may be considered under the following heads : — 187 (1) Insects xi J ^ l.rreaaceous. (2) Parasitic fungi (3) Insectivorous birds. (4) Toads, lizards, etc. (5) Fisli. INSI'X'TS AS NATURAL ENEMTES OF INSECTS. Insects attack and destroy other insects in two ways. When it is natural for one insect to pass all or a part oF its life-cj-cle within the liody of another insect, or within its protective covering, as in that of scale insects, the (ii'st of these is called a parasite ; while the other is called the host. The insect parasites of insects are numerous and ex- tremely useful in i-educing the numbers of injurious species. They very largely belong to two orders, the Uiptera and the Hyiiicnopiera. Tlic parasitic Hynieiioptera form a lai-ge Fig. 176, One of the parasitic hymenoptera. Enhirg,-d. {From U.S. De-i^f. Agric.) group, and vary in size; many of them are very minute, some of them so small as to be scarcely visible to the unaided eye. Not all pai-asitic insects, however, are to l)e considered beneticial from man's point of view, for certain of them 188 attack and destroy other" parasitic insects. These are secondary or hyperpai-asitic, and they are often able greatly to lessen the good effects of the primary parasites. In the second manner of attack, certain insects capture and devour bodily others, generally weaker and smaller than themselves. The insect which obtains its food in this manner is said to be predaceous in habit. Predaceous insects are to be found in nearly all orders, being perhaps Fig- 177. Fiery ground beetle. (a) larva; tfi) adult insect. Nafirnil .s/,-p. {Frotn U.S. Dept. Agric.) most numerous among the Coleoptera. although pond Hies, lace-wing Hies, certain thiips, many Hymenoptera, many Hemiptera, some Diptera and Lepidoptera have this habit of procuring food. Among the Lepidoptei'a it sometimes happens when several caterpillars occur together as borers in a limited space. Among tlie Orthoptei^a the predaceous habit is found in the case of mole crickets, which devour small insects which come within their reach in their under- ground tunnels. Under certain conditions ants are of value as natural enemies of other insects, especially when the victims are out of their natural situation or are wounded and thus unable to escape or defend themselves. Insects which inhabit the soil are quickly attacked by ants if exposed on the surface, and this suggests the practice of ploughing or forking fields in which grubs and similar insects are pests. PARASITIC FUNGI. Parasitic fungi of several species are known as natural enemies of insects. Insects which are fixed in position for considerable portions of the life-cycle, such as scale insects and white fly, and those which have but little free- 189 Fig. 178. Pond flies. A'lildiyrd, (Orifiinul.) dom of movement, such as plant lice, mealy-bug and borer.*, are most subject to attack by fungi, although flies, cotton stainers, moths and grasshoppers are also affected, some- times in such numbers as to materially influence the abundance of these insects. Fig. 179. Moth borer larva attacked by Cordyceps Barberi. {Imjjerial Dept. Agric.) 190 TNSECTIVOEOUS BIRDS. Several species of insectivorous birds occur in the Lesser Antilles. The Barbados blackbird (Qiiiscalus for- tirostris), the tick-bird or old witch {Crotojphaga ani) and the loggerliead are conspicuous examples ; while certain hawks and many smaller birds are largely or partly insect feeders. The blackbirds are vei-y keen hunters for insects. They may often be seen in a corn field, searching the cen- tres of the plants and the tips of the ears for the boll worm and corn ear worm. Avhich they are very successful Fig. i8o. Fungus growing on a moth. (Orii/lnt,/ ) in finding and capturing. They also follow the plough, or labourers forking or hoeing in the field, inspecting the newly upturned earth and greedily devouring the insects and Avorms that are exposed. They may also often be seen picking ticks off cattle on the pasture, and this habit is shared by the tick -bird. The loggerhead is swift of flight and probably captures its prey in the air. Turkeys, Guinea fowls and the common domestic fowl are all keen hunters for insects, which they capture and devour in large numbers. 191 TOADS AND LIZARDS. Toads, called also ciapaud or frog (Bufo agna) are largely insect feeders, and are very valuable in keeping down the numbers of many insects. They feed largely at night, and therefore capture many nocturnal insects but they also feed by day. Toads geiiei-ally recognize their prey by its movements and consequently they rarely, if ever eat, dead or dying insects which may contain fungus or insect parasites. Toads have often been observed to watch an insect such as a cotton worm, h'ing motionless on the ground, for some time, and at the first movement of the insect to snap it up with lightning rapidity. Lizards are largely insectivorous in their feeding habit. The ground lizards in certain islands, and the small green species which are to be seen on trees and plants, are always on the lookout for insects, and if one has the patience to watch for a few minutes they may be observed when stalk- ing and capturing their prey. It is generally believed that in those islands where the mongoose has been introduced, the abundance of many insects is largely due to the fact that lizards, toads and many birds have been killed olT l)y that animal. Many species of fish attack water insects and are specially useful in controlling mosquitoes. .Millions, on account of their small size and greedy appetites, are par- ticularly useful in the West Indies ; but in all localities there are almost certain to be small fish possessing similar habits, which exert a considerable influence on the abundance of mosquito larvae. Fig. i8i. Millions Enlarged. {Imperial Dept. Agric.') 192 INSECTS WHICH ARE CONTROLLED BY NATURAL ENEMIES. While all insects are controlled by natural enemies to a greater or less extent, a few instances may be given to show how this manner of control affects some of the most widely known of our West Indian pests. THE MOTH BORER. The moth borer of the sugar-cane, although it is abundant every year in the West Indies, is probably controlled to a very considerable extent by natural enemies. During the time that the eggs of the moth borer are exposed on the leaf of the cane they are liable to attack by a very small hymenopterous insect. (Fig. 182.) X33. Fig. 182, Hymenopterous parasite of eggs of moth borer. Greatly enlarged. {Imperial Dept, Agric.) The eggs of this insect are deposited in the eggs of the moth borer. The parasite grub hatches and begins to feed on the substance of the moth borer egg, and thus causes the death of the young moth borer caterpillar. Probably many, if not all, moths and butterflies which lay their eggs unprotected in an exposed situation are subject to attacks of this kind by similar parasites. The moth borer is also attacked by a parasitic fungus (see Fig. 179) which .destroys a certain number of the larvae. THE COTTON WORM. The eggs of the cotton worm are attacked by an egg parasite, or perhaps more than one, in a manner similar to that already mentioned in the case of the moth bore;*. The cotton worm is also attacked by a 193 parasite which deposits its eggs within the body of the larva or pupa, where the parasite grubs feed and develop at the expense of the cotton worm. The larger wasps, the cow bee, wild bee and Jack Spaniard are very imi)ortant predaeeous enemies of the cotton worm, in the West Indies. Tlu'se insects build nests of paper ; in these they deposit their eggs and the Fig. 183. Cow bee. EnUinjrd. {Fnnn U.S. Drjif. Ayric.) youug are hatched and reared to maturity in them. The adult insects, of which there are generally several attached to each nest, go in search of food, which they bring to the helpless grubs. Tliis food consists largely of caterpillars, and when the cotton worm is present in large numbers they are very much sought after by these insects. The number of caterpillars caught during a season by wasps is ver}^ great, and it is considered in 8t. Vincent to be due to these insects that the cotton worm has not devel- oped sufficiently to become a pest in that island. It is likely also that many other leaf-eating caterpillars are controlled to a very large extent by these insects. Cotton worms are also eaten by toads and birds ; of the latter, perhaps the most usefid is the blackbird. The ground beetle is known to occur in St. Vincent and Barbuda, where it has been observed feeding on cotton caterpillars. It may occur in other islands, and probably would be a very usefvd check on these insects if it were present in sufficient numbers,, since both the beetle and its grub are predaeeous in habit. 194 SCALE INSECTS. Scale insects are attacked by the para- sitic Hymeiiopteia, which have habits veiy similar to those of the egg parasite mentioned above. The eggs of the para- sites are dejDosited within the body of the scale insect or under its protective covering, and the young grubs which hatch from these eggs feed upon the tissues of the body of the scale insect, or upon the eggs or young. Only a few species of West Indian scale parasites ai-e known ; and the exact extent of their usefulness has not been determined, in the case of most of the scale insects, the amount of fcontrol which ma}^ be exerted by an insect of this kind is well illustrated in the case of the"^ black scale of cotton, or the Hibiscus shield scale, as it is called. The black scale of cotton was a verv serious pest in Bar- bados, in 1905 and 1906. About that time its parasite began to develop very rapidly, and for the past two or three years the attacks of the parasite on the black scale have so com- pletely checked its host that no serious outbreaks of black scale on cotton have been reported. When 'scales are seen with small round holes in them it is a sure sign that the parasites have been present, have completed their life-cycle, and have emerged. It may be taken as a safe supposition that many other scales which do not have the holes in them are parasitized and that the holes wdll appear when the parasites are full-grown and make their escape. Scale insects are also attacked by predaceous enemies— lady-birds, both in the larval and adult stages, attack the young crawling larvae of many species of scales. The larva of the lace-wing fly has a similar habit of feeding on the young of scale insects, and it is likely that these insects play an important part in the control of scale insects. The caterpillar of a small moth feeds upon certain of the larger shield scales, and birds have been observed when they appeared to be eating scale insects. It is not likely, however, that these two last-mentioned natural enemies exert very much control over tlie abundance of scale insects. Parasitic fungi are amojig the important natural enemies of scale insects in the West Indies. The red-headed fungus, the black fungus, and the shield scale fungus all have a wide distribution throughout the West Indies. 195 These fungi penetrate the bodies of scale insects and vau^e tlieir death. The re(l -headed fungus may be recognized by the small orange-red fruiting bodies which are often to be seen attached to the purple scale of the orange and other species. The shield scale fungus forms a fringe of very delicate white growth wliich pi-ojects fi-om inider the bodies of the shield scales. (Fig. 1S5.) Tlic black fungus may be most readily recognized hy the small ))lack patches which it foimsiu the midst of colonies of the white scales sucli as the orange snow scale. These parasitic fungi exert a very considerable intiuence over the numbers of certain species of scale insects, but like most fungi, they make their best develop- ment in a ct)nsiderable amount of moisture, and conse- (juently their influence is greatest in damp loc':^lities and in the wet season of the year. Fig. 184. Syrphus fly. (a)ftn;(b)lnferal view of head : ic) larai. . (From U.S. Drpl. Agrir.) ■h ciifarf/ed. PLANT LICE. Plant lice are attacked by the same kind of natural enemies as those tliat attack the scale insect-:, that is by predaceous insects and parasitic fungi. The predaceous insect enemies of plant lice include tlie lady- birds, the lace-wing and syrphus flies. They are also attacked by the parasitic Hymeaoptera. 196 Fig. 185. Mango shield scale attacked by shield scale fungus. Healthy scales on leaf at left, attacked scales on other Inncs. (Imperial Dept. Agric.) 197 INDEX. Ake»> fringed scale, Asterolecauiuni piistulaiis Alabama aroillacea, Cotton worm Aletia luridula, Lesser cotton worm Ale\'ro(les citri, Citrus white fly — howardi, White fly — nubifera, „ ,, Aleyrodicus cocois, Cocoa-nut white fly Alum Amphiacusta caribbea, House or sick cricket Anastrepha serpentina, Mexican fruit fly Angoumois grain moth, Sitotroga cerealella Anopheles, Mosquito ... Anthonomus grandis, Cotton boll weevil Ants, crazy, Prenolepis longicornis — red or stinging, Solenopsis geminata — sugar, Tapinoma melanocephala ... — white, Termites — wood or carpenter, Caniponotus sp. Aphis gossypii, Cotton aphis ... Application of Insecticides ... Arachnida Argas miniatus. Fowl tick Aromatic oils Arrowroot, pest of ... — worm, Calpodes ethlius Arsenate of lead Arsenic, white Arthropoda ... Aspidiotus destructor, Bourbon aspidiotus — hartii, Yam scale — sacchari, Sugar-cane aspidiotus Asterolecanium pustulans. Akee fringed scale Atomizers ... Auto spray ... 109 38 42 80 81 81 105 178 145 85 156 120 59 14« 146 146 74 146 52 179 4, 5 134 178 92 14. 92 166 166 4 103 112 72 109 184 183 198 Bags, ticklingburg ... ... ... .. . ]85 Banana borer, Toniamis bituberculatuR ... ... ... 112 — , pe.sts of ... ... ... ... ... Ill — weevil borer. tSphenoplionis .soi'fHdn.s .. ... 112 — white % ... ... ... ... ... Ill Barbados leg ... ... ... ... ... 121 Bark borers ... ... ... ... ... ... 81 Barrel spraj^ers ... ... ... ... ... 182 Bean and pea weevils, Bruchns ohinensis and B. qnadriniaculatiis ... ... ... ... 157 Bean leaf roller, Eudamns protens .. ... ...11,114 Beans, Bengal, on limes ... ... ... .. 83 — pe.sts of ... ... .. .. ... ... 113 Bed bug, Ciniex lectidarius ... .,, ... ... 125 'Beetle, cacao, Steirastoma depressnm ... ... ... 86 — cigarette, Lasioderma serricorne ... ... ... 152 — confn.sed flonr, Tril)oliiun confusuni ... ... 156 — drug store, Sitodrepa panicea ... .. .. 153 — saw- toothed gram, Silvanns surinamensis ... ... 154 Bellows, powder ... ... ... ... ... 185 Bengal beans on limes ... ... ... ... 83 Bete rouge, Trombidium ... ... .. ... 129 Black fungus ... ... ... ... ... 77 Black line scale, Ischnaspis longirostris ... ... 105 Black scale, Saissetia nigra ... .. .. ...56,110 ' — parasite of, Zalophothrix mirum ... ... .. 56 Blood-sucking cone-nose, Conorhinus sanguisuga ... 127 Body louse, Pediculus vestimenti ... ... ... 127 Boll weewil, Anthonomus grandis .. .. ... 59 — worm, Heliothis obsoleta ... ... ..49,90 Bonavist ... ... ... ... ... .. 113 Book solution ... ... ... .. ... 167 Bordeaux nozzle ... ... ... ... ... 181 Borer, banana, Tomarus bituberculatus ... ... Ill — bark, ... ... ... ... ... ... 81 — larger moth, Castnia licus ... ... ... 63 — moth, Diatraea saccharalis ... ... ... 60 — orange, Cryptorhynehus sp. ... ... ... 82 — root, Diaprepes abbreviatus .. ... .. 66 — shot, Xyleborus perforans ... ... .. 69 — weevil, Sphenophorus sericeus ... ... ... 64 -- of banana, Sphenophorus sordidus ... ... 112 Boric or Boracic acid ... ... ... ... 168 199 Boui'lxin aspidiotns ... .. ... ... 103 Hot Hies, liorso. (xastrophilus tM|ui ... ... ... 137 cattle, Hypodenna hovis and H. liiieata ... ... 137 — sheep, Oestinis ovis .. ... ... ... 136 Brassolis isthmia attackinjji; cocoa-nut ... ... ... 109 — sophorae ., ,, ... ... ... 1013 Brncluis cliineusis and B. «]uadriiuaculatua l)ean and pea weevils ... ... 157 Bucket sprayers ... ... ... .. ... 18-1 o. Cacao beetle, Steirastoma depi-essuin .... ... ... 8fi — pests of ... ... ... ... ... ... 8() — thrips of, Heliothrips rubrocinctus ... ... 87 Calandi-a granaria, granary weevil ... ... ... 154 — oryza, Kice weevil . . ... ... ... 154 Calosonia caliduni. Hery ground beetle ... .. ... 41 Calpodes ethlius ... ... ... ...14,92 Camphor ... ... ... ... ... ... 177 Camponotus sp., wcod or carpenter ant .. ... 146 Cane Hy, Delphax saccharivora ... ... ... 70 Carbon bisulphide ... ... ... ... ... 174 Carbolic acid ... ... ... ... ... 178 Castnia daedalus, attacking cocoa-nuts in Surinam ... 109 — licus, larger moth borer .. ... ... 63,108,112 Cat, and dog flea, Pulex serraticeps .. ... ... 124 Cattle tick, Margaropus austi'alis .. ... ... 131 Centipede, a myriapod ... .. ... ... 7 Cephalosporium lecanii, Shield scale fungus ... ... 78 Ceratitis capitata, Mediterranean fruit fly .. ... 84 Chaetocnema araazona, sweet potato flea beetle... ... 100 Chaff' scale, Parlatoria pergandei ... ... ... 77 Chalcis annulata, Hymenopterous parasite ... ... 41 Chigger flea, Sarcopsvlla penetrans .. ... ... 125 Chilocorus cacti, spotted lady-bird ... ... ... 103 Chionaspis citri, orange snow scale ... ... ... 76 Chi tin, exoskeleton ... ... ... ... ... 4 Chrysomphalus aonidum^ red spotted scale ... ... 78 — aurantii, orange red scale ... ... ... ... 79 Cigarette beetle, Lasioderma serricorne ... ... 152 Cimex lectularius, bed bug ... ... ... 125 Circulation of insects ... ... ... ... ... 18 Citrus fruits, insect pests of ... ... ... ... 75 . — — , scale insects attacking ... ... ... 75 200 Citrus white fl}^ Aleyrodes citii ... ... ... 80 Clothes moth, Tinea spp. ... ... ... ... 152 Coccus viridis, gt-een shield scale ... ... 78, 110 Cockroaches... .. ... ... .. ... 142 Cocoa-nut mealy-bug, Pseudococcus nipae ... ... 104 — snow scale, Diaspis boisduvalii ... ... ... 103 — white Hy, Ale3'rodicus cocois ... ... ... 105 Cocoa-nuts, pests of ... ... ... ... ... 103 — , scale insects attacking ... ... ... ... lOB Coleoptera ... ... ... ... ... ... 29 Common mealy-bug, Pseudococcus citri ... ... 110 Compsomyia niaceDaria, screw worm ... ... ... 134 Confused flour beetle, Tribolium cont'usnm ... ... 156 Conorhinus sanguisuga, blood-sucking cone-nose ... 127 Contact poisons ... ... ... ... 163,176 Contarinia gossypii, flower-bud maggot ... ... 45,46 Control of insects ... ... ... ... ... 160 Corn ear- worm Laplygma frugij^erda ... ... ... 51,90 Corrosive sublimate ... ... ... ... ... 166 Cjtton, pests of ... ... ... ... ... 38 aphis ... ... ... ... ... ... 52 — scale insects ... ... ... ... ... 58 — stainers ... .. ... ... ... ... 43,44 — worm, Alabama argillacea ... ... ... 88 Crab louse, Phthirius inguinalis ... ... ... 127 Crazy ant. Pienolepis longicoinis ... ... ... 146 Creasote ... ... ... ... ... ... 178 Cricket, house or sick, Amphiacusta caribbea ... ... 1^5 Crude oil and whale-oil soap ... ... ... ... 173 Crustacea ... ... ... ... ... ... 4 Cryptorhynchus batatae, scarabee or Jacobs ... ... 96 — sp., orange borer ... ... ... .. 82 Cucumbers, pests of ... ... ... ... 115 Culex, mos(|uiro ... ... ... ... ... 120 Cut worm, cotton ... ... ... ... ... 54 , tobacco ... ... ... ... ... 95 Cyanide of potassium ... ... ., .. 176 Cylas formicarius, sweet potato weevil ... ... 102 Dacus tryoni, Australian fruit fly ... ... ... 84 Dalmatian insect iJowder ... ... ... ... 169 Dtjlphax saccharivora, cnne fly ... ... ... 70 201 Dermanyssus gallinae, poultry mite, nimbles ... ... 139 Diaphania hyaliuata. melon moth ... ... ... 115 Diaprepes abbreviatus, root boror ... ... ... t>6 Diaspis boisduvalii, cocoa-nut snow scale ... ... 103 Diatiaea saccharalis, moth borer ... ... ... 00 Digestion in insects ... ... ... ... 17 Diptera, flies ... ... ... ... ... 32 Dog tick, Rhipicephahis sp. ... ... ... ... 133 Domestic animals, pests of ... ... ... ... 131 Dragon flies, Odonata ... ... ... ... 26 Drosophila ampelophila, ripe-fruit fly ... ... 158 Drug store beetle, Sitodrepa panicea ... ... ... 153 Dysdercus androae, cotton stainer ... ... ... 43 — delauueyi, cotton stainer ... ... ... ... 44 — fernaldi „ „ .. ... ... 44 Ectobia germanica, German cockroach... ... ... 144 Eel worms, nematodes ... ... ... ... IK) Elephantiasis, Barbados leg ... ... ... ... 121 Epitrix parvula, tobacco flea beetle ... ... ... 95 Eriophyes gossypii, leaf-blister mite ... ... ... 47 Eudamus proteus, bean leaf -roller ... ... ...11,114 Euthrips insularis, sweet potato thrips ... ... 101 Euthisanotia amaryllidis ... ... ... .. 118 Exoskeleton, chitin ... ... ... ... ... 4 IF. Fiery ground beetle, Calosoraa calidum ... ... 41 Filaria ... ... ... ... ... ... 120 Flat-winged insects, Platyptera ., ... .. 27 Flea beetle, tobacco, Epitrix parvula ... ... ... 94 Flea beetle, sweet potato, Chaetocnema amazona ... 99 F'leas ... .. .... ... 123,124,125,138 Flies, bot, Gastrophilus equi, Hypoderma bovis, H. lineata, Oestrus ovis ... ... 136,137 — , fruit, (keratitis capitata, Trypeta ludens, Dacus tryoni, Anastrepha serpentina ... 84, 85 — , ripe fruit, Drosophila ampelophila ... ... ... 158 Flour beetle, confused, Tribolium confusum ... .. 156 Flower-bud maggot, Contarinia gossypii ... ... 45-46 Fly, house, Musca domestica ... ... ... ... 128 202 Fly, Warble, Hypoderma bovis Fowls, itch mite of, Sarcoptes nuitaiis ., Fowl tick, Argas miniatus Friiiged-winged insects, Th^'sanoptera . Fruit Hies (see Flies, fruit) — — ripe, Drosojjhila ampeloiDliila Fumigants ... Fungus, black, Myriangium Duriaei — red-headed, Sphaerostilbe coccophila — shield scale, Cephalosporium leeanii .. — white-headed, Ophionectria coccicola &. Gastrophilus equi, horse bot Girardinus poeciloides, Millions Glassy star scale, Vinsonia stellif era Grain beetle, saw-toothed, Silvanus surinamensis — moth, Angoumois, Sitotroga cereallella — weevils, Calandra granaria and C. oryza Grasshopper, Shistocerca pallens Green fly, aphis — scale. Coccus viridis Grey mealy-bug of sugar-cane, Pseudococciis saechai-i Growth of Insects Gryllotalpa didactyla . . Guinea corn Gun-powder ... HI. Half- winged insects, Hemiptera Head louse, Pediculus capitis ... Hellebore, Veratrum album Heliothis obsoleta, boll worm ... Heliothirps rubrocincta, cacao thrips Hemichionaspis minor, white scale, cotton Hemiptei^a, half-winged insects Hexapoda, insects Hog louse House cricket, Amphiacusta carilibea ... — flea, Pulex irritans — Hy, Musca domestica ... 203 Household in?. eots ... ... ... ... ... 142 Hymoiioptera, iiiem))raiie-\vinged insects ... ... 34 Hypodornia lineata. warble Hy, or cattle hot ... ... 1^7 I. Indian corn, pests of . ... ... . . ... 90 Insecticides ... ... ... ... ... ... l')2 — , application of ... ... ... ... ... 171) — , price list of ... ... ... . . ... I7!t In.sectivorous Uirds ... ... ... ... ... 190 Insect powder, Dalmatian, Persian, Pyrethrum ... ... 168 Insects and their near relations ... ... ... 4 natin-al enemies ... ... .. ... 186 — , circulation of ... ... ... ... ... 13 — , digestion of ... ... ... ... ... 17 — , growth of ... .. ... ... ... 9 — , natural enemies of ... ... ... ... 187 — , natural history of... ... ... ... ... 9 — , nervous system of .. .. ... ... ... 16 — , orders of ... ... ... ... ... 2 1 — , reproduction of ... ... .. ... ... 19 — , respiration of ... ... ... .. ... 14 — , senses of ... ... .. .. ... 12 — , structure of ... ... ... ... 9 I.schnaspis longirostris. black line scale .. -.• lOo Itch mite of fowls, Sarcoptes mutans ... ... ... 140 J". Jack Spaniard, Polistes annularis ... ... .. 41 Jacobs or Scarabee, Cryptorhynchus batatae ... .. 96 Jigger ilea, Sarcopsylla penetrans ... ... ... l25 Kerosene emulsion ... ... ... ... ... 172 Key to the Orders of Insects ... ... ... ... Si) Knapsack sprayer ... ... ... ... ... 183 Lady-bird, spotted, Megilla maculata ... ... ... 54 — , Chilocorus cactus ... ... ... ... 103 Lantana bug, Orthezia insignis ... ,.. ... 79 204 Laphygma frugiperda, corn ear- worm ... ... ... 51, 90 Larger moth borer, Castnia liens ... ... ...03,108 Lasioderma serrieorne, Cigarette beetle... ... ... 152 Lead arsenate ... ... ... ... ... 166 Leaf-blister mite, Ei-iophyes gossypii ... ... ... 47 Leaf-roller, bean, Endamns proteus ... ... ...11, 114 liegislation and Imported Plants ... ... ... 162 Leaf-cutting bee ... ... ... ... ... 119 Lepidoptera, scale-winged insects ... ... ... 28 Lepidosaphes beckii, purple scale ... ... ... 75 Lepisma sp. ... ... ... ... ,., ... 145 Leptostylus praemorsus, Lime tree bark borer ... ... 81 Leptus americanus, Bete rouge ... ... ... 130 — irritans. Bete rouge ... ... ... 130 Lesser cotton worm, Aletia luridula ... ... ... 42 Lice ... ... ... ... ... ... 127 — , poultry, Menopon pallidum ... ... ... 139 Lime trees, Bengal beans on . . . ... ... ... 83 Lime, white ... ... ... ... ... ... 178 London purple ... ... ... ... ... 166 Malaria ... ... ... .. ... ... 120 Man. insects which attack ... ... ... ... 120 Margaroi)us annulatus australis, cattle tick ... ... 131 Meal moth ... ... ... ... ... ... 154 — woims ... ... . . ... .. ... 154 Mealy-bug, cocoa-nut, Pseudococcus nipae ... ... 104 — , common, Pseudococcus citri ... ... ... 110 — , grey, sugar-cane, Pseudococcus sacchari .. ... 73 — , pink, sugar-cane, Pseudococcus calceolariae ... 71 Mealy shield scale, Pulvinaria pyriformis ... ... Ill Megachile martindalei ... .. ... ... 119 Melon moth, Diaphania hyalinata ... ... ... 115 Membrane- winged insects, Hymenoptera .. ... 34 Menopon ])allidum, poultry louse ... ,. ... 139 Metamorphosis ... ... ... ... ... 10 Millions, Girardinus poeciloides ... ... 122, 191 Millipede ... ... ... ... ... ... 7, 8 Mite, itch of fowls, Sarcoptes mutans ... ... ... 140 — , leaf-blister, Eriophyes gossypii ... .. ••• 47 — , poultry, Dermanysus galliuae ... ... ... 189 — , rust, Phytoptus oleivorus ... ... ... 82 Mole cricket ... ... ... ... ... 117 '205 Mosquitoes ... ... • • ••• ... 126 Moth, Angoumois grain, Sitotroga cerealelJa ... ... 156 — borer, Diatiaea sacc'hari . . ... ... .. 60 — larger, Castnia liens, ... ... ... ...63,108 — clothes, Tinea sp. ... ... ... ... 152 — meal ... ... • •• •■• ... 154 — melon, Diaphania hyalinata ... ... ... 115 — wooly pyrol, Thermesia gemmatalis ... ... 113 Musca domestica, house or tyi)hoid fiy ... ... 128. Myriangium Dnriaei, Black fungus ... ... ... 77 Myriai)oda ... ... • • ... .•• ... 4, 7 3sr. Natural history of insects ... ... .. ... 9 Napthalene ... ... .•• ... ... 177 Nematodes, eel worms ... ... ... ... 110 Nerve-winged insects, Neuroptera ... ... ... 28 Nervous system of insects ... ... .. ... 16 Neuroptera, nerve- winged insects ... ... ... 28 Nimbles, chicken mite ... ... ... ... 189 Nozzle, Bordeaux ... . . ••• ... ... 181 — Vermorel ... ... .-- .. ... 180 Nutmegs, pests of ... ... .-. ... ... Ill o. Odonata, pond flies ... ... ... ... ... 26 Oestrus ovis, sheep bot ... ... ... ... 136 Oils, aromatic ... ... ... ... ... 178 Ophionectria coccicola white-headed fungus ... ... 76 Orange borer, Cryptorhynchus sp. ... ... ... 82 ■ — red scale, Chrysomi)halus aurantii ... ... 79 — snow scale, Chionaspis citri ... ... ... 76 — Avorm, Mexican, Trypeta ludens... ... ... 84 Orders of insects ., ... -.. ... ... 21 Orders, key to ... ... ... ... ... 35 Orthezia insignis, Lantanabug . . ... ... 79 Orthoptera, straight-winged insects ... .. ... 21 IP. Palm weevil, Rhynchophorus palmarum ... ... 107 Parasitic fungi ... ... ... ... ... 188 Paris green ... ... ... ... ... ••• 164 206 Parlatoria pergaudei, Chaff scale ... ... .•• 77 Pea and bean weevils, Bruchus ehinesis and B. qiiad- riraacvilatus ... ... ... •• 158 Pediculus capitis, head louse ... ... ... ••• 12^ — vestimenti, body louse ... ... .. ... 127 Periplaneta americana, American cockroach ... ... 143 — australasiae, Australian cockroach ... ... HS Persian insect powder .. .. ... ... 1(J8 Phosphorus ... ... ... ... .. ••• 168 Phthirius inguinalis, crab louse ... ... ... 127 Phytoptus oleivorus, rust mite ... .. ... 82 Pink mealy-bug, Pseudococcus calceolariae ... ... 71 Platyptera, flat- winged insects ... ... ... 27 Poison bait ... .. ... .. ... ••• 55 Poisons, contact ... ... ... ... 163, 170 Poisons, stomach ... ... ... .. ... 164 Polistes annularis, wild bee, Jack Spaniard . ... 41 Polistes bellicosus, cow bee ... ... ... ... 190 Porricondyla gossypii, red maggot ... ... .. 52 Potassivim cyanide .. ... .. ... 176 Potatoes, sweet, pests of .. ... ... ... 96 Poultry lice, Meno])on pallidum ... ... ... 139 — mites, Dermanyssus gallinae .. ... ... 139 Powder gun ... ... ... ... ... 185 — bellows .. ... ... ... ... ... 185 Prenolepis longicornis, crazy ant ... ... .. 146 Price list of insecticides ... ... ... 179 Prodenia oniithogalli, cut worm ... ... ... 51 Protoparce cingulata, potato moth . ... ... 98 — sexta, tobacco worm ... ... ... ... 93 Pseudococcus caleolariae, pink mealy-bug ... ... 71 — citri, common mealy-bug ... ... ... .. 110 — uipae, cocoa-nut mealy-bug ... ... ... 104 — sacchari, grey mealy-bug ... ... ... ... 73 Pulex irritans, house flea ... ... ... ... 123 — serraticeps, eat, and dog flea ... ... ... 124 Pulvinaria pyriformis, mealy shield scale .. ... Ill Purple scale, Lepidosaphes beckii ... ... ... 75 Pyrethrum ... ... ... ... ... ... 169 Red or stinging ants, Solenopsis geminata .. .. 146 — headed fungus ; Sphaerostilbe coccophila ... ... 70, 81 — maggot, Porricondyla gossypii ... ... ... 52 76 207 Ked scale, orange, Chrysomphalus aurantii — spidei-, cotton, Tetranyclius gloveri ... ... 7,58 — — , sweet potato, Tetranychus telarius ... ... 101 — spotted scale, Clirysomphalus aoniduni ... ... 78 Repellents ... ... ... ... ... ... 1{)3 Reproduction in insects ... ... ... ... 19 Resi)iration in insects ... ... ... ... 14 Rhynchophorus palniaruni, [)ahn weevil ... ... 107 Ripe-t'ruit flies, Drosophila spp. ... ... ... 158 Root borer, Diaprepes abbreviatus ... ... ... (56 Rosin ... ... .. ... ... ... 171 Rubber, pests of ... ... ., ... ... 109 Rust mites, Phytoptus oleivorous ... ... ... 82 s. Saissetia nigra. Black scale of cotton ... ... ... 50 — — , parasite of, Zaloi^hothrix mirum ... ... 56 Sarcopsylla penetrans, Jigger ... ... ... 125 Sarcoptes mutans, itch mite of fowls ... ... .. 140 Saw-toothed grain beetle, Silvanus surinamensis ... I55 Scale insects, cotton ... ... ... ... ... 56 Scale- winged insects, Lepidoptera ,.. ... ... 28 Searabee or Jacobs, Cryptorhynchus batatae ... ... 96 Schistocerca pallens. grasshopper ... ... ... 73 Scorpion ... ... .. ... .. ... 5 Screw Avorm, Compsovayia macellaria ... ... ... I34 Senses of insects ... . ... ... ... 19 Sheath-winged insects, Coleoptera ... ... ... 26 Sheep bot, Oestrus ovis ... ... .. ... 136 Shield scale fungus, Cephalosporium lecanii ... ... 78 — — mealy, I'nlvinaria pyriformis ... ... ... Ill Shot borer, Xyleborus ])erforans ... ... ... 69 Sick or house cricket, Amphiacusta caribbea . ... 145 Silvanus suiinamensis, saw-toothed grain beetle ... 154 Silver fish, Lepisma ... ... ... ... ... 145 Sitodrepa panicea. Drug store beetle ... ... ... 153 Sitotroga cerealella, Augoumois grain moth ... ... 156 Snow scale, cocoa-nut, Diaspis boisduxalli ... ... 103 — — orange, chiouaspis citri ... ... ... 76 Solenopsis geminata, red or stinging ant ... ... 146 Sphaerostilbe coccophila, red-headed fungus ... ... 76,81 ■Sphenophorus sericeus, weevil borer ... ... ... 64 — — sordidus, banana borer ... ... ... 112 208 Spiders Spotted lady-bird Sprayers, auto — , barrel ... — , bucket ... — , knapsack — , power ... Stegoiuyia fasciata, yellow fever mosfiuito Steirastoraa depressum, cacao beetle . . . Stinging ant, Solenopsis geminata Stomach poisons Stored products, insect pests ... Straight-winged insects, Orthoptera . . . Structure of Insects ... Sturmina distincta, parasite of potato worm Sugar ant, Tapinoma melanocephala ... Sugar-can(t aspidiotus, Aspidiotus sacchari — — , pests of Sulphur Sweet potato flea beetle, Chaetocnema amazona , pests of , red spider, Tetran ychus telarius . . . — — , thrips, Euthrips inaularis , weevil, Cylas fornjicarius , worm, Protoparce cingulata Syntomeida syutomoides Syringes T. Taeniotes scalaris, borer in Castilloa Tapinoma melanocephaluni, sugar ant ... Telenonnis, parasite ... Termites or white ants Tetranychus gloveri, cotton red spider ... — telarius, potato red spider ... Thermesia genimatalis, woolly pyrol worm Thrips, cacao, Heliothrips rubrocincti ... Thrips, sweet potato, Euthrips insuiaris Thysanoptera, fringe-winged insects Ticks — , cattle, Margaropus annulatus australis — , dog, Rhipicephalus ep. — , gold, Amblyomma variegatum 209 icks, fowl, Argas iiiiiiiatus 'ickliii<;l)urg hags inea spp., clothes moths oads and li/ards bhacco - and soap ... - ilea heetle, E[)itiix {)arvula worm, Protoparce sexta bniarus hituhercidatus. Banana horer ... I'iholium eont'nsnm, confused fioui- beetle ricliom-annna pretiosa, [)arasite in egj^'s of cotton worm and moth borer rombidium, B6te rouge I'vpeta ludens, Mexican orange worm . urpentine ... wo- winged insects, Diptera ... ... 134 185 15'^ ... 191 109 ... 173 95 93 ... 112 ... 156 41, 62, 92 ... 129 84 ... 178 32 ■V". Veratrum album, Hellebore Vermorel nozzle A^iusonia steJlifera, glassy star scale 170 180 104 "VT". "\Varl)le tly, Hypoderma bovis, H. lineata Weevil, l)ean and pea, Bruchus chinensis and B. quadri- maculatus — borer, Sphenophorus sericeus — — of banana, Sphenophorus sordidus ^, granar}^, Calandra granaria • Weevil, palm, Rh^aichophorus pahiiarum — , sweet potato, Cylas formicarius Whale-oil soap and rosin compound ... and crude oil... Whip scorpions White ants, Termites ... — arsenic — hy, citrus, Aleyrodes citri ... — — , cocoa-nut, Aleyrodicus cocois — headed fungus, Ophionectria coccicola — scale of cotton, Hemicliiouaspis minor Wild bee, Polistes annularis 74, 137 157 64 112 154 107 102 170 171 173 5 149 166 80 105 7G 58 41 210 Woolly pyrol moth. Thermesia genimataiis Worm, arrowroot, Calpodes ethlius — . l)oll, Heliothis obsoleta — , corn ear, Lapliygma frugiperda Worm, cotton — , cut, Prodenia ornithogalli — , eel, Nematodes ... — , lesser cotton, Aletia luridula — , meal — , orange, Trypeta ludens — , screvv^, Compsomyia macellaria — , sweet potato, Protoparce cingulata — , tobacco, Protoparce sexta. 113 14,92 49,90 51.90 38 54 116 42 154 84 134 Xyleborus perforans, shot borer 69 Yams, pests of — , scale, Aspidiotus hartii Yellow fever mosquito, Stegomyia fasciata 112 112 120 z. Zalophothrix mirum, parasite of black scale 56