JLAPAZ ,-\_ B 0 ' i I V ' 1 (Ja (:ocHABA>leASA^StAcRuz , 'ORURO^ > F0T05I / C^^^5;-^ w/^ B R A / Z I L Fig. o. — Map showing re.oioiis occupied l)y ScJiistocejX'ct para )ie 11 sis duviuif the winter months of 1896, 181)7 and IS'JS as indicated by data gathered by the .Sub-commission.
6 therefore, be taken into consideration when limiting the distribution of this insect. Especially is this liable to be true with reference to records for Ecuador and central Brazil. Habits. — Nothing further has been added to our knowledge concerning the habits, wintering or egg-laying. Though on this last mentioned topic considerable effort has been made to decide whether or not each female insect deposits but a single cartuclto, or several cartuchos of eggs at intervals during the spring and summer months. Neither has the data thus far obtained enlightened us as to whether or not a partial second brood is reared in the northwest provinces late in the fall — during the months of April and May. Bj^ compiling the data accumulated on this point and covering a period of something over three years it is found that only 12 records occur of egg-laying during the month of August, 78 records for September, 326 records for October, 116 for November, 10 for December, 14 for January, 9 for February and 5 for March, while for April there occurs no definite record and but a single one for May. From these figures it can readily be seen that egg-laying occurs chiefly in spring, and for that matter mostly within 40 or 45 days with the month of October as the height of the season. This fact in itself would jDoint quite conclusively that the rule must be but a single brood as well as a single cartucho of eggs per female. The irregularity noted later in the year could be readily accounted for by the supposition of retarded development of the eggs in many females that had become weakened either by disease, accident, or climatic influences during winter or early spring and later recovering sufficientlj' to migrate and develop their eggs.
The late layings in the northwest provinces are as jqX, hard to account for unless we are led to believe as Mr. Oliver C. James intimates in a letter. ''From Rioja and Catamarca reliable reports of locusts depositing eggs in February and March were received. These were, doubtless, the progeny of the mangas which were hatched in these localities at a little later jjeriod last year. ' '
Flights. — But little additional data of such a nature at least as to change what has been recorded under this head has accumulated during the intervening period. Mr. W. G. Davis, of the Meterorological Bureau, Cordoba, has submitted the following remarks :
"A few general considerations in connection with the flight of locusts which I think we may assume as facts: — 1st, that in the southern Hight in si3ring, the locust travels much faster than it does on the return Hight in the autumn, or latter part of summer. ::^nd. In the spring it generally flies during the warm hours of the day, when it takes advantage of the greater velocity of the wind : whereas, on its return to the North, it rises about sunset, travelling in the hours when there is little if any wind. ord. The direction of the flight in regard to the direction of the wind varies according to the velocity of the wind.
"Now, keeping these facts in view (provided they are such) let us look at the salient features of the wind condition, taking our Cordoba results a characteristic of those prevailing over the larger part of the Pamj)a region, and these will practically hold good for the region to the north and northwest from whence the locusts start in the Spring. ' 'We note that the maximum movements for both the north and south winds takes place in the months of August and September, so that at the season when the locust is leaving its hibernating grounds, it would be just as easy for him to make his way north as south, /. e., the wind would help him as much on one course as on the other : thus, it would seem that it is purely instinct that leads the locust back to the region where it was produced, also that it shapes the course like a sailor both in flying before it and tacking and is in a hurry to reach his destination, making shorter stops on the journey and travelling in the hours when the wind will most assist its flight. I may be entirely wrong in the above supposition — I do not assert them as facts — but merely l^resent them for your consideration."
Natural Enemies. — Birds, Insects and other Ani-
8 MAL8. — In the letter accompanying the data accumuhitecl by the Sub-commission Mr. Oliver C. James, of Carcarana, F. C. C. A., writes as follows concerning' some of the natural enemies of the locust :
' 'There was also a marked increase in the number of birds, and the toads in all j^arts of this province particularly appeared in almost alarming numbers, so that the work of destruction carried on by these unobtrusive friends of the agriculturist was quite an appreciable factor in the w^hole country. The most noticeable feature in this increase of locust destroyers was the number of beetles (Trox — "claiiiiiil''^) to be found wherever the egs's w^ere deposited. Almost as soon as the female locust began perforating the ground, certainly immediately after the eggs were laid, the cJidiiiin put in an appearance, and as many as 20 to 30 of the beetles had been seen at work by close observers, in the earth about one 'bed' or cluter of 'cartuchos. ' " Among the specimens of these champies that were collected by the writer or by the various correspondents of the Commission during his sojourn in Argentina, the three following species have been recognized; viz., Trox f^uberof^us Fabr., Trox aeger Guer., and Trox piUulttrhis Germ. These occur throuhgout the entire Pampa region, and their numbers are in the order named. They are a natural check to locust increase that appears to be uncontrollable by man, and there can be little doubt of their value in this direction. Mr. James also adds that "From nearly every point reports indicate the presence of the long thread-like w^orm * {3Ier)fns or Gordu'iH) and the short stocky grub (Tachina fly, — "Jachim") in the body of the locust — both in the saltona as well as in the voladora. The latest reports regarding the recently winged locust state that many are infested with the 'guzano' (the fly larva.)" *l)r. H. H. Ward of the University of Nebraska, who is a re.'oyiiizeil specialist on this lii-ou}) was to have prepared a i)aper foi- tliis report on the above nicntioncd worm. Init was prevented from dointf so on aeeount of press of otlier duties.
9 In addition to the insect enemies of ixiriieii^is mentioned in former reports, it migiit be of interest to know that at least one species of the larii'e bluish wasps with yellow wings of the o-enns Pcpsis is known to attack it. Master William Thomas, a very careful observer of insects at Carcarana, informed the writer that on more than one occasion he had seen these large wasps dash into a cluster of saltonas and sting one after the other, and then deliberately select one from among them and malve off with it. Since there are several species of the genus J^epsi.s to be found at that locality the exact species was not determined.
Fi^. 5. — Deail saltmias of ScJiistucerca parauensis covei'ed with the ( 'nrcaiaim Funtrus.
Functus Diseases. — Nothing further of note seems to have developed concerning the effectiveness of the different insect attacking fungi as a means of combating this insect.
10 At least two such fungi have frequently been observed to attack it, and at times, with such persistence as to materially lessen the hordes of insects in certain localities. Up to the present time, however, no definite favorable reports have been received of its successful artificial distribution. Mr. James writes that "Experiments made with the 'funous Carcarana' gave no definite results, although the season was favorable for the action of the fungus, having been humid almost continuously. There have been no mangas of locusts infesting the immediate locality of last year's development of the fungus disease, but between this jDlace and San Geronimo the evidence of hundreds of dead locusts from a manga which was detained by stress of weather indicates that the fungus had developed there, all being of the characteristic bright red colour and more or less desicated, notwithstanding the prevailing moist condition of the atmosphere."
This would indicate that the fungus is still active in the country, and that, under the proper conditions will take hold of and destroy locusts. The SchiHtocerca paranenHhseems to be most subject to its attack, since but three other species were found killed by it during the writers careful search for others while in the country. These were ZonioiKxIa farsata, Diponthm^ comiinotns and Bichrop/us clo)i(jatus all of which are more or less abundant and inclined to become destructive at times. These insects are figured in the second portion of the present report.
Other sjDecimens of the destructive locust that had evidently been killed by another of the fungous diseases were encountered by correspondents of the commission. Mr. James writes that "several specimens of locusts were sent to you by mail which had evidently died from the effects of the growth of an external fungus of a light ash colour, which almost completely enveloped the after part of the body. This had been observed as a cause of death during several years previous to your coming to the country, but none were reported here during the period of your investigations. "
11 Just what this last mentioned fungus is has not been ascertained, since the specimens above referred to must have been lost.
The South African locust disease has been tried with but poor results, save as reported in connection with the destructive locust of that country.