THE INSECT FAUNA OF THE GENUS CRATAEGUS 1055 



the blossom clusters have just begun to separate and before the blossoms 

 show pink. They puncture the leaves and the tender twigs but do not 

 cause any noticeable injury. After the fruit sets they feed on the fruit 

 also and cause very slight dimples where they puncture it. They become 

 adult in late May and early June, and begin ovipositing in the twigs 

 about June 15. The egg is deposited in a small slit mad 9 with the beak at 

 the base of a young twig. Adults were found on the trees until late July. 



mendax Reuter, Lygidea (Bright apple redbug) 



A few nymphs of Lygidea mendax were found feeding on the leaves and 

 fruit of Crataegus in late April and in May. They are not so common 

 as Heterocordylus malinus. In the warm laboratory the eggs hatched on 

 March 27 on Crataegus punctata twigs, but no nymphs were found in the 

 field until the blossoms were opening on April 25. Adults were found 

 from June 2 to August 14. One adult in a breeding cage oviposited on 

 June 19 in a twig of Crataegus crus-galli. She chose a year-old twig, 

 drilled a hole through the bark at the base of the twig, and then, turning 

 about, thrust an egg into the cavity. 



ornatus VanD., Orihotylus 



A few adults of Orthotylus ornatus were found feeding on the leaves of 

 Crataegus pruinosa in June. They are brownish, spotted, slender, and 

 5.5 millimeters long. 



ostryae Knight, Lygus 



A few adults of Lygus ostryae were taken puncturing the leaves of 

 Crataegus punctata in late June. They are pale yellowish brown, and are 

 otherwise similar in appearance to the tarnished plant bug. 



pellucida Uhl., Diaphnidia 



The pale green nymphs of Diaphnidia pellucida are rather numerous on 

 the foliage of Crataegus punctata during late May and early June. They 

 run rapidly over the branches when disturbed, and feed on the leaves 

 and tender 4wigs. Adults appeared from June 10 to June 15 in rearing 

 cages in the laboratory, and others were found in the field on Jun3 18. 

 They are delicate, slender, pale green, and about 4 millimeters long. 



pratensis Linn., Lygus 



Adults of Lygus pratensis which have lived through the winter are some- 

 times found puncturing the buds of Crataegus in April, as soon as the buds 

 show green, and a few were found puncturing the young fruit in late May. 



univittatus Knight, Lygus 



Adults of Lygus univittatus are rather common during late May and 

 June, puncturing the leaves and fruit of native hawthorns. They resemble 

 L. communis very closely, but are generally paler. 



