THE STATE ENTOMOLOGIST. 



35 



THE HAELEQUIN CABBAGE-BUG.— .S'^rac/urt [Murgantia} histnonica, 



Halm. 



(Hpteroptera, Scutelleridic.) 



Prior to the year 1870 the insect 

 which forms the subject of this sketch 

 was not known to occur in Missouri. It 

 has of late years been gradually travel- 

 ing towards us from the more southern 

 States, and has already made its presence 

 a little too manifest in some of our south- 

 ern counties, and in Kansas I have met 

 with it at a latitude higher than St. Louis. 

 It extends to Guatemala, and is found in 

 Mexico ; and it varies very much, as most 

 species are found to do when their geographical distribution is studied. As 

 it extends southward we find the dark colors predominating, and becoming 

 more intensified and brilliant, and Stal has described a species (Murgantia 

 mmida) from Mexico, which is doubtless but a geographical race, since all the 

 intermediate grades occur between it and the more northern form of histri- 

 onica. My ft-iend, Mr. P. E. Uhler, has made some interesting experiments 

 on the species, which have clearly proven that when reared in the dark the 

 pale red parts predominate; while if reared in the bright day-light, the dark 

 blue colors predominate. I gave a short account of it in the American Ento- 

 mologist (Vol. II., pp. 79, 80), and cannot do better than repeat that account 

 here with such modifications and additions as are necessary to render it 

 more complete. 



Cabbage-growers in the North are apt to think that the plant which 

 they cultivate is about as badly infested by insects as it is possible for any 

 crop to be, without being utterly exterminated. No sooner are the young 

 cabbages above ground in the seed-bed, than they are often attacked b}^ sev- 

 eral species of Flea-beetles. By these jumping little pests the seed-leaves 

 are frequently riddled so full of holes that the life of the plant is destroyed; 

 and they do not confine themselves to the seed-leaves, but prey to a consid- 

 erable extent also upon the young rough leaves. After the plants are set 

 out, the larva3 of these insects are found upon the roots, in the form of tiny 

 elongate six-legged worms. Through the operations of these subterranean 

 foes, the young cabbages, especially in hot dry weather, often wither away 

 and die ; and even if they escape this infliction, there is a whole host of cut- 

 worms ready to destroy them with a few snaps of their powerful jaws; and 

 the common White Grub, as we know by experience, will often do the very 

 same thing. Suppose the unfortunate vegetable escajjes all these dangers of 

 the earlier period of its existence. At a more advanced stage in its life, the 

 stem is burrowed into by the maggot of the Cabbage-fly (Anthomyia bras- 

 sicce) — the sap is pumped out of the leaves in streams by myriads of minute 



