31 



Fig. 10. During the winter these bugs, full grown, remain in a torpid state,, 



■^^^ / secluded in nooks and crevices, from whence they issue during the first 

 \\/V* warm days of spring. As soon as the vines of the squash have put forth 

 a few leaves, the female bug begins to lay her eggs, which she does chiefly 

 /" wHL V depositing them in little patches on the underside; the eggs being 



/^H\ gl^ed to the surface. There, in a few days, they hatch into young bugs, 

 r BP j which at once begin to suck the sap from the leaves by means of their 

 \ K proboscis, which is thrust into the leaf for this purpose. The young are 



^ short and plump, of a pale ash colour, and emit the same disagreeable 



odour as that which characterizes the parent. During their growth they shed their skins 

 several times, gradually developing wings and retaining their activity throughout until 

 they attain to the perfect winged state. At first they live together in little swarms on 

 the underside of the leaves, which in consequence of the numerous punctures of the in- 

 sects, and the quantity of sap imbibed by them, soon wither and appear as if scorched by 

 fire. When the leaves have been exhausted in this way, they are deserted for fresh 

 ones, and thus the work of destruction goes rapidly on. 



The eggs are not all laid at one time, but like the Colorado potato beetle, the eggs 

 and young may be found in their various stages of development throughout the summer. 



The perfect bug measures six-tenths of an inch in length, is of a blackish colour 

 above, and a dirty ochre-yellow beneath, while the sharp lateral edges of the abdomen 

 which project beyond the closed wing covers are spotted with ochre-yellow. The thin 

 overlapping portion of the wing cover is black, the wings transparent, but dusky at 

 their tips. 



To prevent the ravages of these insects they should be sought for early in the season 

 and destroyed before they have an opportunity of laying their eggs. To this end they may 

 be looked for about the last of June or beginning of July, when the dusky creatures may 

 be found under the leaves on the ground, or on the stems of the vines close to the ground. 

 If eggs have been laid they should be sought out and crushed. A short time spent in 

 this way early in the season will save much disappointment afterwards. 



The Oyster-shell Bark Louse of the Apple-tree (Aspidiotus conchif&rmis ). 



The spread of this insect which is represented in figure 11, seems to depend very 

 Fg. 11. much on the nature of its surroundings. If it finds its way into an orchard 

 where the soil is damp and the drainage imperfect, and the roots of the trees 

 consequently unhealthy, the stunted and weakened growth which naturally 

 results, is very favourable to the spread of this pest, and in such locations it is 

 not uncommon to see branches of trees almost entirely covered with them, 

 while other trees on adjacent higher ground will be almost or quite free from 

 their attacks. Within the last two or three years we have several times found 

 them attacking the branches of pear-trees, but in these instances their increase 

 seems limited, and they do not thrive as on the apple. In Prof. Riley's fifth 

 Annual Report, he states that they attack the currant, plum, pear, cherry and 

 apricot. On the twigs of the apple, when allowed unmolested possession, they 

 multiply in amazing numbers, and notwithstanding their extreme minuteness 

 individually, yet by their constant and combined efforts in sucking the juices 

 of the tree, they induce such a diseased state of the branches as is very discour- 

 aging to witness. 



The name " Oyster-shell Bark Louse," has in this instance been suggested by 

 the form of the scale which closely resembles that of an elongated oyster-shell. In 

 colour it is ashen gray, much like the bark to which it is attached. This scale 

 is formed by the mother-insect from exudations from her body during the summer, and 

 about the end of August or beginning of September there will be found a quantity of very 

 minute eggs beneath each scale. Having completed her work, the parent dies, but the 

 eggs remain under the scale all through the winter until the following spring. Early in 

 June, but sometimes, if the season is backward, a little later, the eggs hatch and produce 



