REPORT OF THE ENTOMOLOGIST AND BOTANIST 



179 



' Pea Bug.' 



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Fig. 3. — The Pea, Moth : caterpillar and moth — 

 2 and 4 enlarged. 



SESSIONAL PAPER No. 16 



is preferable because better known in the trade for what students of insects call 

 the Pea Weevil ; a few have even insisted that the Pea Weevil is what is really 

 the Pea Moth. The name Pea Weevil, as applied by entomologists, is undoubtedly 

 the correct name for the short roundish hard beetle which is found among seed peas 

 from NVhich it has emerged, leaving a perfectly round hole in the hollowed out 

 pea where it passed its preparatory stages. This insect is shown enlarged and 

 of the natural size at figure 2. The name Pea Weevil is claimed by entomologists 

 to be correct for this insect, because it belongs to a family of beetles the technical 

 name of which is weevils, and, moreover, it has always been known for nearly a 

 hundred years by this name. There is, however, no particular objection to the use of 

 tliQ trade name Pea Bug, notwithstanding its inaccuracy (the insect not being a bug, 

 nor in any way resembling one), because there is no true bug which is a serious enemy 

 of the pea, and therefore no confusion arises from speaking of the Pea Weevil as the 

 The Pea Moth, shown at figure 3 in the perfect form, which, however, is 



very seldom seen, is a small slaty-gray moth, 

 ' three-eighths of an inch in length, resembling 



somewhat in markings but not in colour the 

 Codling Moth. This insect is generally seen 

 by pea growers when in the caterpillar state 

 (figure 3 : 1 and 2), when it is usually called 

 ' the worm,' and frequently does a large 

 amount of injury to the pea crop of Canada, 

 chiefly, however, in districts lying east of 

 the area infested by the Pea Weevil and in- 

 creasing in severity as the Atlantic sea-board 

 is reached. The small white caterpillars 

 live inside the green pods, attacking the 

 peas by gnawing ragged-edged cavities into them and filling up the pod around their 

 cavities with a mass of excrement. As tliis insect is less known to pea growers and 

 seed merchants than the Pea Weevil, and as the name Pea Weevil is also somewhat com- 

 paratively new to them, it having only been brought prominently forward during the 

 last twenty years, during which efiforts have been made to counteract insect attacks, I 

 think it probable that the confusion which has arisen in the minds of some who have 

 not studied insects, and who have applied the name Pea Weevil to the Pea IMoth, has 

 been due to their having applied the unfamiliar name Pea Weevil to the unfamiliar 

 insect which they knew was not their ' Pea Bug,' with which they were well acquainted. 

 The third insect which has drawn attention by the extent of its injuries and which 

 like both of the above is frequentl}'' spoken of as ' the bug,' is the Destructive Pea Aphis, 

 which is a soft-bodied plant-louse about ^ of an inch in length and expanding about ^ 



of an inch when the wings are opened. This is 

 pale bluish green in colour with the legs dark- 

 ened at the joints and with very long honey 

 tubes at the end of the abdomen. The Destruc- 

 tive Pea Aphis appeared suddenly for the first 

 time in the summer of 1899, and practically 

 ruined the pea crop over large areas in the 

 United States and Canada. Since that time it 

 has become less in numbers and during the past 

 season was only reported in a few places upon 

 late peas and upon sweet peas in gardens. Per- 

 haps the worst attack was upon Grass Peas 

 which were much belated this season and upon 

 Hairy Vetch and field peas which had been sown for ploughing down as green manure. 

 To recapitulate, the Pea Weevil or ' Pea Bug ' (Fig. 2) is a small beetle, the grub 

 of which lives inside the pea until fully developed, and the beetle emerges in autumn or 

 the following spring through a perfectly round hole. 

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Fig. 4. — The Destructive Pea Ajihis : winged 

 vivip.arous teniale — enlarged G times. 



