October ii, 1893.] 



Garden and Forest. 



423 



part of the dock and sold by the truck-load, an average price 

 for this grade being at present twenty-five cents a bunch. 

 A truck of the lower grades of fruit, of which there is more 

 than of number one, is filled in fifteen to twenty minutes, 

 and a half-minute only is needed to bid it off. A rise of 

 two and a half cents a bunch is recognized in the bidding, 

 and there are fixed rates of cartage. The entire work is 

 transacted with the greatest dispatch, as many as 4,000 

 bunches being unloaded m an hour. The buyers, among 

 whom Italians, Greeks and Hebrews outnumber the Ameri- 

 can dealer, are ranged along the taffrail of the steamer, 

 overlooking the trucks as they are loaded, and the general 

 animation is occasionally heightened by good-natured 

 shouts or groans on the announcement of a specially good 

 or bad purchase. Upon delivery to the buyer the bananas 

 are stored in dry cellars, those intended for early use being 

 suspended in an air-tight compartment, where they are 

 ripened by heat from gas-stoves. 



As much as ninety-five percent, of the fruit received here 

 is of the yellow variety; all the red bananas, which were 

 formerly held in high favor, being received from Baracoa. A 

 few of the small "lady-finger" bananas, of singularly deli- 

 cate and delicious fiavor, are occasionally had from Aspin- 

 wall, and are highly esteemed for table use here as they are 

 in the tropics, where they are greatly preferred and are 

 generally used. They do not carry well, and for this 

 reason are seldom seen here. tx/t n t> 



New York. -^W- ^- ^• 



Entomological. 

 Notes on Blister-beetles. 



ALMOST every season brings with it some unexpected 

 development of insect activity, and often, without any 

 reason that we can discover, insects which had never be- 

 fore figured as injurious will suddenly increase to enor- 

 mous numbers, or take on new habits, and demand active 

 interference to prevent serious harm. These sudden irrup- 

 tions are often as short-lived as they are unexpected, and 

 an insect, after having been injurious one or two years, may 

 sink back into insignificance, and for years thereafter will 

 not again be heard of. One factor which we recognize as 

 favoring the increase of certain species is the weather ; 

 either the temperature or the relative amount of moisture, 

 or both. Thus, we have learned by experience, that a dry 

 season favors the development of the Orthoptera, grass- 

 hoppers, crickets, locusts, katydids and the like, and where 

 two or more dry seasons follow in succession, we may 

 have a destructive increase. Almost as a matter of course, 

 where any insect increases abnormally, its parasites and 

 other natural enemies will also increase, either in like or 

 greater proportion ; but they are unable, except in rare in- 

 stances, to conquer the host. As a rule, parasitic insects, 

 and those forms that are predaceous, may be counted 

 among our friends ; but this rule is subject to some impor- 

 tant exceptions, and to one of these reference will be made 

 here. 



The seasons of 1891 and 1892, and particularly the latter, 

 were very favorable to the development of grasshoppers, 

 and, therefore, it was to be expected that their natural ene- 

 mies should abound. Among the most effective of these 

 are certain blister-beetles, members of the family MeloidcC, 

 which in the early stages feed in the egg-pods of some of 

 the grasshoppers. In the larva state these insects are dis- 

 tinctly beneficial, and they destroy a large percentage of 

 the grasshopper-eggs that are laid. Unfortunately, these 

 beetles in their adult stage change their habits, and, instead 

 of feeding upon animal tissue, feed upon vegetation, and, 

 therefore, must be classed with the injurious forms. While 

 many species confine themselves to plants of little value to 

 the agriculturist, others feed upon almost anything that 

 comes in their way ; or they may even prefer plants that 

 have an economic value. During the season of 1893 the 

 Potato was one of the plants that suffered from the attacks 

 of blister-beetles. In several of the eastern states there 



were complaints of injury from them, and generally the 

 statement was made that they appeared very suddenly, and 

 in very large numbers. It was usually stated, also, that 

 poisons had no effect upon them. From some localities 

 the insects were received with the note that these were ex- 

 amples of the "old-fashioned Potato-beetle" which was 

 occasionally injurious before the Colorado-beetle became 

 known as "the" Potato-beetle. 



A brief life-history of these insects may not be without 

 interest. So far as we know anything of the early stages 

 of the Meloidae, they are parasitic, not only upon Orthop- 

 tera, as already suggested, but also upon Hymenoptera, 

 and particularly upon certain bees. Those species that be- 

 came troublesome to potatoes are, I believe, all of them 

 parasitic upon grasshoppers, or rather upon grasshopper- 

 eggs. The beetles make their appearance about the time 

 that their hosts begin to lay eggs, and they themselves de- 

 posit their ova in likely places in the localities in which the 

 grasshoppers are most numerous. From these eggs there 

 emerge in a short time active little creatures known as Tri- 

 ungulins, which are able to live for some days without 

 food, and spend their time searching for a grasshopper-egg 

 pod. When such a one is found, the larva enters it, changes 

 its character and appearance completely, and from an ac- 

 tive becomes a sedentary type. It assumes a grub-like 

 form and continues to feed until the entire egg mass is 

 consumed, being itself then full-grown. It reaches this con- 

 dition long before it is time to change to the adult form, 

 and it then assumes what has been called the coarctate 

 state. In this condition it rests quietly without feeding, the 

 outer skin hardened, and remains until just before the time 

 when the adult usually emerges ; then it again becomes 

 active, casts this hardened outer coating in which it has 

 lived so long, and again becomes an active creature, re- 

 maining in this form only for a very short time, prior to 

 changing into a normal pupa. From this point the trans- 

 formation takes place as is usual in the order; but, as in 

 the case of some other species that became mature some 

 time prior to their appearance as adults, the conditions that 

 lead to their development act upon almost the entire brood 

 in exactly the same manner, and much the largest percent- 

 age will emerge at about the same time. This accounts 

 for their sudden appearance, and in a field where on one 

 day not a specimen was observable, there may be thou- 

 sands upon thousands the day following. The beetles are 

 quite voracious feeders, and usually by the time that farm- 

 ers have realized their presence they have done a large pro- 

 portion of damage. Poisons may be applied, and they are 

 undoubtedly effective, but even the arsenites act slowly 

 upon this type of insect, and for two or even three days 

 thereafter they will continue their feeding, thus giving rise 

 to the belief that the poisons have no effect upon them. 

 Besides potatoes, beets and beans are favorite food-plants 

 of the blister-beetles, and for sometimes a week, matters 

 will look bad for the crop ; then the insects will disappear 

 almost as suddenly as they arrived, and nothing further 

 will be seen of them. 



We have here one of those curious cases in which it is a 

 little questionable as to what shall be done. Should these 

 insects be considered as injurious, or as really beneficial .'' 

 That they are an important factor in checking grasshopper 

 increase there can be no question, and the only one re- 

 maining is. Does the injury done by the beetles over- 

 balance the benefit derived from the larva-? In a general 

 way, and in most cases, we can say positively that it does 

 not, and that it would be better to suffer the injury done 

 by the adults for the benefit of the advantage to be derived 

 from the larvae. This is especially true in the western 

 states, where grasshoppers are very much more numerous 

 and destructive than they are in the east. As the question 

 is one which ma)^ be decided otherwise by the farmer most 

 concerned, the next point is. What would be the best 

 method of preventing injury? and here I think that poi- 

 sons are not generally indicated ; but that collecting in 

 pans or in umbrellas is very much the better and more cer- 



