A lady-bird. The word is found in Grose, 1787: N.E.D.

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1837.  

        The Lady-Bug sat in the rose’s heart,
  And smil’d with pride and scorn,
As she saw a plain-drest ant go by,
  With a heavy grain of corn.
Lydia H. Sigourney, ‘The Lady Bug and the Ant.’    

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1848.  [The flamingo] drinks nothing but port wine, and is partial to lady-bugs.—Durivage and Burnham, ‘Stray Subjects,’ p. 115.

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1910.  Los Angeles, April 1.—Millions of ladybugs are receiving free transportation on the railroads from the State Insectary at Sacramento to the melon fields of the Imperial valley. Three consignments have passed through Los Angeles en route to El Centro, and other valley points, where they will be turned loose to browse upon aphides and other insect pests that harm the melon crops. There are on hand in the insectary at Sacramento 52,000,000 ladybugs, weighing in the aggregate more than a ton. These are to be distributed free among farmers who apply for them.—N.Y. Evening Post, April 4.

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