314 



THE AGRICULTURAL NEWS, 



October G, 1906. 



INSECT NOTES. 



Caterpillars on Sweet Potatos. 



During bis recent visit to St. Kitt's, Mr. H. A. Ballou, 

 Entomologist on the staff of the Imperial Department of 

 Agriculture, visited a field of sweet potatos at Lodge estate 

 that had been attacked by large caterpillars a short time 

 before. 



The attack had first been noticed on the lower or down- 

 liill side of the field which was several acres in e.xtent, and 

 the caterpillars began quickly working their way across the 

 field, entirely stripping the vines of leaves, and making 

 rapid progress. The potatos belonged to certain peasants, Avho 

 would not undertake to carry out any recommendations 

 as to remedial measures, and were, at first, unwilling that any 

 poison should be applied to the jiotato leaves. ^Ir. F. R. 

 Shepherd, Agricultural Superintendent, however, arranged 

 for a trial of Paris green, and a stri|i covering six rows across 

 the field was treated to a liberal dusting of Paris green and 

 lime at the rate of 1 to 6, in precisely the same way that 

 cotton is dusted for the control of the cotton worm. None 

 of the caterpillars, so far as could be seen, crossed this strip, 

 enormous numbers being found dead on the ground among 

 the vines to which the poison had been aiiplied. 



At the time of his visit Mr. Pallou found the lower 

 side of the field putting out new leaves to a certain e.xtent, 

 but the recovery had been verj' .slight and the difterence 

 between the two piortions of the field, that which had been 

 attacked and that which had not, was very marked. 



This case is a verj' strong one in illustration of the 

 beneficial results of the prompt use of Paris green, which 

 was also shown in dealing with caterpillars on cassava in 

 St. Lucia, as mentioned in the Agricultural Keios, Vol. V, 

 p. 298. 



The caterpillar attacking sweet potatos in St. Kitt's 

 was probably Frotnparce cin;/iil'itus, but as the larvae and 

 moths were not found, the identification depended on the 

 ai)pearance of the pupa. 



Food Plants of Cotton Stainers. 



In the paper on cotton stainers which appeared in the 

 Wed Indian Bulletin (y6\. VII, pp. 64-8.5), and was reviewed 

 in the Agriculticral News (Vol. V, p. 218), a list of the food 

 plants of these insects was given. This list includes all the 

 plants then known to be attacked by these insects. Cotton 

 stainers (D^/sdercus andreai) have recently been found feeding 

 upon a wild malvaceous plant growing on the mountains in 

 Nevis, the name of which has not yet been determined. 



It is greatly desired to get information as to any 

 additional food plants of these insects, and any notes which 

 might be submitted by readers of the Ag) n-ultural Netcs 

 would be much appreciated. 



Specimens of leaves and ttowers of such plants, as well 

 as of insects, might be forwarded through the local officers of 

 the Imperial Department of Agriculture. 



Lady-birds. 



A correspondent in Barbados has sent to the office of the 

 Imperial Deiiartmeut of Agriculture a number of larvae and 

 pupae of the common red lady-bird [Ci/r/oiicda mnguinea), 



with the statement 

 „^ J, that they are abund- 



^00 



Fit:. 19. Lady-bikds. 



ant on young cotton 

 and a query as to 

 whether these insects 

 are likely to do the 

 cotton harm. 



It is probable 

 that more careful 

 observation would 

 have disclosed the 

 cotton aphis in con- 

 Spotted lady-bird {Me,fdh, mucuhda) ; sjderable numbers on 

 Red lady-bird (('iichnnhi .stiHjriti'/ieu) ; this young cotton, 

 c. Eggs uf ladybird. All enlarged, and the lady-birds 



would then have 

 been seen to be feeding on the aphis. 



The lady-bird beetles commonly found in the cotton 

 fields have been frequently described in the Agricultural A'ews^ 

 and in Vol. IV, p. 298, illustrations were given which show 

 the appearance of the adult beetle and the larva. These 



;., 



Fii;. 20. Eggs .<nd L.\kv,\e. 



II., Egijs, and '<., larva, uf lace-wing fly ; ( 

 lady-bird. All enlarged. 



larva of 



figures are again inserted. Fig. 19 .shows two forms of lady- 

 bird commonly found in cotton fields. The larva of a lady- 

 bird is shown in fig. 20, c. 

 The lace-wing fly, whose eggs 

 and larva are illustrated in fig. 

 20, is also a beneficial insect. 



Fig. 21 shows the cotton 

 aphis upon which the lady- 

 birds and the lace-wing fly feed. 



The aphis does not very 

 often become destructive ; it 

 generally attacks young cotton, 

 but cotton which is healthy 

 and growing ra[)idly will 

 generally out-grow the aphis Much 

 attack. It will usually be found 

 on the very young shoots and 



tender leaves, large numbers of them being closely packed 

 together. This same aphis attacks several other plants, 

 and from these cotton may become infested. 



It is desirable that all who are engaged in cotton cultiva- 

 tion should become familiar with the beneficial in.sects, as 

 well as with the pests, in order that the forreer may be 

 recognized as friends of the, planter and that no apprehension 

 may be felt when they are found in the cotton fields. 



Fig. 21. Cotton Aphis 



enlarged. Natural size- 

 indicated by hair-line. 



