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Mr. E. A. Schwarz of the U. S. Bureau of Entomology), as well as larvæ, probably of this species, have been taken in areas where the "southern grass worm" was abundant. A single adult of a smaller species of Carabid was reared from a larva taken at Rio Piedras near poisoned bait, where dead larvæ of Laphygma were present.

Lizards probably feed on the larvæ and adults and may be important enemies of the species.

Two species of blackbirds occur in Porto Rico, known locally as "el chango" or "mozambique" (Holoquiscalus brachipterus) and "el Judio" (Crotophaga ani). Both of these blackbirds undoubtedly do a great deal of good in reducing the numbers of caterpillars, particularly those occurring in the more open grasslands.

RESULTS FROM THE USE OF POISONED BAIT. On January 13, 1912, an experiment was made with poisoned bran at Rio Piedras. Onefourth pound of Paris green and ten pounds of bran were mixed and enough water, sweetened with molasses, added to make the particles of the mixture adhere. The compound was placed in small piles on ground, very free from vegetation, between a field of grass, in which the "grass worms" were very plentiful, and a plot of young cane which they were apparently just beginning to attack. Larvæ, largely those of Laphygma frugiperda, found dead around the piles on January 16, were referred to Dr. F. W. Zervan, chemist of this station, for analysis, and he later reported that their bodies gave a decided arsenic reaction. In connection with the outbreak of "grass worms" in the La Plata region, the writer was told that poisoned bait, the composition of which was not learned, distributed in a furrow through a field of grassland, had destroyed larvæ "by the hatful."

A NOTE ON "THE GRASS LOOPER," Remigia repanda Fab. Where outbreaks of the "southern grass worm" occur the larvæ are often accompanied by the larvæ of Remigia repanda. In the area attacked at Rio Piedras during January, 1912, the larvæ of Laphygma frugiperda appeared to predominate, though they did not greatly exceed "the grass looper" in numbers. While the two species occurred together, one or the other prevailed in sections of the whole area. At the other points where outbreaks occurred, no data was obtained on the relative abundance of the two species, the larvæ having, for the most part, pupated at the time visits were made to these areas.

As has been mentioned, the larvæ of Laphygma frugiperda prefer to work among the opening leaves of the cane, while those of Remigia repanda work upon the unfolded leaves, the older as well as the younger portions of the plants being eaten. When the food supply becomes scanty, however, this difference in feeding habits is less pronounced.

PEACH "STOP BACK" AND TARNISHED PLANT BUG

(Lygus pratensis Linn.)

By LEONARD HASEMAN, Department of Entomology, University of Missouri

For many years the nurserymen of Missouri as well as those of other states have been confronted with injury to peach and pear buds in the early spring. This injury has been laid to various causes. Some attribute it to the work of thrips, others to mites and in some cases it has been supposed to be due to soil conditions. A number of papers during the past year have appeared in which the relation of the tarnished plant bug to this injury has been carefully discussed. In the writings of some of the earlier entomologists we find brief discussions of the importance of the tarnished plant bug with reference to the destruction of buds and to the injury it does to fruit and plants in general. It is not strange, therefore, that we should suspect this insect and attribute to it at least a part of the injury to peach and pear buds.

For the past two years the writer has been following the injury commonly spoken of as "stop back" of peach here in Missouri and finds that the tarnished plant bug is responsible for this injury. The injury is worse some seasons than others and seems to be worse in certain parts of fields. Invariably it is the more thrifty growing nursery stock which suffers most and this is usually in the damper parts of the nursery blocks and where the soil is richest. During the past spring this injury was probably as noticeable in certain sections of Missouri as it has even been known to be in this state. Some seasons the injury begins to appear soon after the dormant buds in budded peach stock begin to push out but fortunately the past summer it did not occur until the first week in June after the young growth had advanced from eighteen inches to two feet and therefore was not especially destructive, though in some portions of the infested blocks nearly all of the growing buds were killed. This injury occurs all of a sudden and the agent of destruction seemingly disappears from the nursery almost as suddenly.

The study of this pest is being carried on at the Experiment Station and in one of the nurseries of central Missouri. The nurseryman notified the writer on June 7, three or four days after the first severe signs of the pest appeared, and on arriving at the nursery it was found that but few bugs still remained in the nursery, but on visiting adjoining fields of clover, timothy and weeds it was found that they were present in great swarms, especially in clover where they were at work

depositing eggs. The writer learned that with the first appearance of the wilting of the buds these same swarms of tarnished plant bugs were present in the nursery blocks and from this and from later experiments with a view of determining the effect of the feeding of this pest upon peach buds, there can be no doubt but that in Missouri the tarnished plant bug is the source of its injury to young peach buds. The peach twig borer is often very troublesome in Missouri, especially on older trees but very little of its injury occurred in this nursery. The block of peaches found to be worst attacked stood alongside a forty-acre field of clover which was in full bloom when the writer visited the nursery. This clover was cut and cured a week later which evidently destroyed the majority of the eggs deposited by the tarnished plant bugs, for at no time later in the season were they so abundant in this field or in the nursery though in other fields they were plentiful all summer.

The writer has not had any opportunity of making a careful study of the early spring activity and development of this insect, but it would seem that on emerging from its winter quarters the pest is especially fond of the sap of peach and pear, but that after the first brood of eggs are deposited in the spring, the insect, like some of the orchard plant lice, prefers to feed upon the sap of other plants where the eggs are deposited, so that in this latitude at least it seldom returns to the nursery in destructive numbers.

The writer has had an opportunity of following the pest through the late summer and fall months and has learned a number of interesting facts with reference to the insect and its activities during that part of the year. It was found that the tarnished plant bug does not deposit its eggs in the tissue of plants as some maintain, not even in the soft stems of weeds. The ovipositor of the tarnished plant bug does not seem to be sufficiently strong to enable it to drill into tissues of plants. In this region it deposits its eggs, in the fall of the year at least, only in the blossoms of flowers such as daisies, asters, "mare's tail" (Erigeron canandensis), etc. This latter weed is used very largely for the depositing of eggs in the fall. The nymphs as well as the adults feed upon the sap of this plant during the month August, September and October. They continue to breed until the first heavy frosts have completely killed out driven them into winter quarters. It is not uncor

pest feeding as late as the first of November up

places. After frosts have destroyed most one can find the tarnished plant bugs co gardens, feeding upon the sap of turni type which are more resistant to fros

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to be found by the thousands in and among the leaves of mullen plants where in this latitude they crawl about on warm days during the winter. Judging from the number of tarnished plant bugs which have gone into winter quarters, we may expect very severe injury to nursery stock in the spring.

A study of the development of the tarnished plant bug during the fall months has proven most interesting. In these studies the writer finds that the pest completes its cycle in thirty to thirty-five days during the months of September and October and he is of the opinion that during the summer months the life cycle is completed in from twenty to twenty-five days. It has been found that the pest has five distinct nymphal stages in place of four, as has always been maintained, therein agreeing with other closely related Hemiptera. It is not strange that the one nymphal stage has been overlooked by other workers, for it was not until a great many specimens had been followed from the egg through the first three nymphal stages, that the stage which has always been overlooked was finally discovered. The confusion is with the first three nymphal stages. The writer soon found that he had a nymph which in size, shape and markings did not agree either with the newly hatched nymph or the stage figured by other writers as the second nymphal stage. For a time it was considered as the early second stage but when it was found that it molted on assuming the form of the supposed mature second stage, it was clear that this was a distinct stage. This was confirmed over and over later with first stage nymphs. In a number of cases the writer has been able to carry individual specimens of the insect from the freshly laid egg through the five nymphal stages to the adult form. The life cycle and development of the tarnished plant bug will be discussed more in detail in another paper.

The subject of the control of the tarnished plant bug is one that deserves special attention for the injury to nursery stock alone is very considerable each year and the damage to vegetables and small fruits is not to be overlooked. This insect will probably never be controlled by any one method though by resorting to a number of simple mods of insect control it can be kept in check. During the

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nd fall all weeds and other blooming plants which proosition and food for the young and old insects royed. Fence rows, roadsides and waste lands

grounds for this insect and they should be or all infested weeds should be sprayed regutact wash. Hundreds of tarnished plant bugs gle isolated weed during the summer months. boring places of the hibernating adults should be

burned over and mullen and other partially green plants which harbor the insects should be carefully destroyed. In the spring trap crops can probably be used to advantage in protecting nursery stock though this will require futher investigation. When the adult tarnished plant bugs are at work in the nursery a machine, provided with sticky shields, something similar to the one used for the apple leaf-hopper, is very effective in catching them. They are much more active than the leafhopper but where such a machine has been used in a nursery it catches thousands of the tarnished plant bugs. The writer is inclined to doubt the feasibility of protecting peach stock by spraying, at least with any of our present-day insecticides.

THE APPLE LEAF-HOPPER

(Empoasca mali LeB.)

By LEONARD HASEMAN, Department of Entomology, University of Missouri

To nurserymen growing apple trees on an extensive scale this pest is often one of the most troublesome, especially in the more northern section of the Middle West. It has for years caused great trouble to nurserymen throughout the northern half of Missouri and in the last season or two has shown signs of becoming troublesome in the nurseries, even of the southern part of the state. In those nurseries where it has become established it is exceedingly injurious to the young stock and difficult to control. Aside from reports by Mr. Webster, issued recently by the Agricultural Experiment Stations of Iowa and Minnesota, we have little in the way of definite records concerning this pest, its life cycle and means of controlling it.

For the past two years it has been under observation by the writer in one of the larger nurseries of this state. We have not succeeded in making much progress relative to the life cycle and habits of the pest throughout the summer months, but we have determined some facts and have arrived at a definite scheme which seems to prove entirely effective in keeping the insect under control. We are told that the pest passes the winter in the egg condition under the bark of apple trees in the more northern states. From observations and experi ments in Missouri it would seem that the pest is never carried over the winter in this condition, but, similar to the grape leaf-hopper, it passes the winter in the mature stage hiding about rubbish, along fence rows and under the foliage of such plants as docks, turnips and others, the foliage of which is not always completely destroyed by the first frosts of winter. Trees taken from the worst infested

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