138 



THE AGRICULTURAL NEWS. 



May 



1908. 



INSECT NOTES. 



The Hemiptera or True Bugs. 

 Ill the Agricultural A'eics from time to time (see 

 Vol. VI, pp. 10(j, 218, 261), 29«) there have appeared 

 short sketches dealing with groups of insects in which the 

 general characters of the older or family have been given, 

 and mention has been made of certain West Indian forms 

 likel}- to be well known on account of their habits, or 

 any peculiarity or special beauty in thiir appearance. 

 TLe Hemiptera include many diver.se forms of many 

 habits. The name of the order means lialf-wing and was 

 given on account of the |iecuHar apijearance of those members 

 of tlie order who have the outer wings thickened foi- a portion 

 of their length (say one half) while the i-fniainder, the termi- 

 nal iiortion, is thin and niembranou.s. The Hemiptera have 

 sucking mouth parts, and undergo incoiiijiletc luftaniorphosis. 

 The Hemiptera are divided into three large groups. 

 One of thesf contains insects which in their habits are (larasi- 

 tic on man and other mammals. The.se are low forms w hirli 

 have no wings, such as the lice and bed-bugs. 



A second group is called the Heini|itera Homoptera, in 

 which the outer wings are membranous for their whole length. 

 To this group belong the scale insects (Coccidae), the white 

 flies (Aleyroilidae), the lace bug.s, the leaf hoppers, tlie plant 

 lice (Aphidae), and others. 



The thiid group contains the Hemiptera in whieh the 

 wings are typical as desca-ibed above ; they are called Hemip- 

 tera Heteroptera. 



PerhalJS the most al)Uiidant and the most ini|ioitant from 

 an agricultural point of view are the scale insects. Nearly 

 everyone in the West Indies is familiar with these insects, or 

 with the results of their work. Scale blight, as it is often 

 called, attacks neiudy every kind of |)lant growing in the 

 tropics. The .scale insects on the citrus fruits and on cotton 

 are perhaps as well known as any. 



In this family is found - still a further e.\coiiti(iu t.. tlie 

 wing arrangement. The female is wingless and the male has 

 only one pair of wings. 



The white flics (Aleyrodidae) are closely related to the 

 .scale insects. One species {A/';i/r(i(li;i> cltri) is fairly common 

 on citrus trees and, in liaTbados at least, another species 

 {A/(;>/)-orlirii.< Cofoix) occurs:on the cocoa-nut, and others on 

 a variety of palni.s, banana, fiddlcwood, and other plants. 

 The aphids or [plant lice arc akso common and are at 

 times serious pests. The cotton aphis, ami the aphis of rose 

 and many other garden plants are all well known. 



Among the Hemiptera licteroptera are to be iudndcd 

 the cotton stainers {Dyxilnriix -spp.), the green pea chink 

 {Xezara tilridnht) which is cominou on pigeon peas and 

 often found on cotton, the large brown bug (•S/Mrfuirni /Kff.i), 

 which is sometimes found oi;i tomato and other Solanaceous 

 [dants, the water striders, water boatmen, and others. 



Although most of the mendiers of this latter group are 

 jilant fejders, .some are predaceous on other iiM-i-ts and a tew 

 even attack man. The most common of these latter is the 

 blood-sucking cone-nose {Coiiorhiiittx .<a)i:/<n.<ii;/iix) which 



iiitiicts a veiy painful sting with its proboscis. The wheel 

 bug {Arihis rrist'itiis) is one of the largest of the tree bugs. 

 The thorax is much arched longitudinally in a .sharp curved 

 ridge which is toothed like a saw. This insect is predaceous 

 and, in this way, useful. 



There is an insect which is frequently found in cotton 

 fields and mistaken for a cotton stainer and which is I'reda- 

 ceous on other insects. Care should be taken by the cotton 

 grower to distinguish between them. 



As the Hennptera are well provided with sucking mouth 

 parts, Paris green and other similar stomach poisons are use- 

 less. Scale insects, plant lice, etc., must be killed by mean.«i 

 of contact jioisons, such as kerosene, whale oil soap, petroleum, 

 rosin, etc. Directions for making up these solutions and 

 applying them have been published from time to time in the 

 Ai/n'rii/fiii/il yen:\ and are to be found in the bo(dclets 

 ' Scale Insects of the Lesser .Antilles,' Farts I and II, Nos. 7 

 and •J2 in the Pamphlet Series issued by the Imperial Depart- 

 ment of .Vgriculture. 



INCREASED USE OF ARTIFICIAL 

 MANURES IN EGYPT. 



The United States Consul-General at Cairo draws 

 attention to the increasing imports of artificial niannres 

 into Eg\[it. While the quantity shipped to Egypt 

 from South America in 1904 was only 20 tons, it 

 increased in 1906 to 2.798 tons, valued at S186,o00. 



The Consid .states that the above increase is due partly 

 to the greater area of cultivable land, owing to the Assouan 

 Dam and other irrigation works, and partly to the fact that 

 the peasant cultivators are endeavouring to grow cotton 

 once every two years instead of once in three, and are 

 beginning to realize that it is neces.sary to restore to the .soil 

 the nourishment taken from it by the cotton. 



The chemical manures used, with average prices per ton 

 .-. i. f., Alexandria, including the packing of the manures in 

 double sacks, are as. follows : Nitrate of soda, •'?60-S8 ; 

 .sulphate of ammonia, .•*(').•)• ."51 to •■5(U-.5;i : superphosphate, 

 ^1.5-10 to .'7l()-07. 



The only manures maiiiifactund in Kgypt are sewage 

 and slaughter-hou.se products wmked up by the Cairo Sewage 

 Transjiort Company, for which a good market is found. The 

 market for chemical manures is open to any manufacturer 

 Ml- merchant, as there is no monopoly for the import of 

 artificial fertilizers, and also because the Government has 

 ceased lending money to the Khcdivial Agricultural Society at 

 a low rate of interest, i.e., 2 \m- cent, per annum. 



The im|iorts of chemical manures are allowed duty free 

 into Kgypt, and there are special reduced rates on the State 

 railways for carriage into the interior. 



( 'idle is the principal .source for nitrate of .soda : 

 licluiiini for .su|ierpliosphates, and Glasgow is the main port 

 of >lii|inii-nt for sulphate of ammonia. 



Castilloa Rubber Seed. In view of a prospec- 

 tive demaml tor Castilloa rubber seed during the coming 

 .season, it may be mentione<l that the Curator of the Dominii-a 

 Hotanic Station expects to have about \2 or 15 It), of seed 

 available after meeting tiie local demand. At Montscrrat, 

 the Curator anticipates that he will be able to snjiply about 

 10 lb. of seed from the Castilloa trees at the station. This 

 rnliber .seed slmnld be worth about .5.<. per H)., packed. 



