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In southern Indiana and other southern States, larvae of L. hurmeisteri, 

 L. guercus, L. antennata, etc., which pupate in spring, emerge as adults 

 during the same season, in June or July. The related species, Ligyrus 

 gibbosus and L. relictus, require one year for development. The larvae 

 feed on manure and other decaying matter, but the adult of L. gibbosus 

 attacks the roots of Amaranthus and Helianthus and may cause some 

 damage. Cyclocephala immaculata may become a serious field pest, 

 attacking the same crops as Lachnosterna. It has a one-year cycle ; 

 pupation takes place in spring and adults emerge in June and July. 

 Cotalpa lanigera is of importance in some districts, since it injures 

 raspberries, strawberries, maize, grass, etc. The hfe-cycle occupies 

 four or five years. Polyphylla variolosa in New Jersey has a similar 

 life-cycle to that of the preceding species. The distinguishing 

 characters of the larvae of Lachnosterna and the above-mentioned 

 related species are described. 



Field observations have shown that some species of Lachnosterna 

 occur at certain elevations, others where certain soil conditions exist, 

 and others where a particular food-plant is available. L. tristis, 

 L. hirticida and L. fmterna feed in the adult stage on hickory and oak, 

 L. fusca on ash, while L. gibbosa is a general feeder. Most species 

 prefer a clay-loam soil, but L. prunina occurs only on sandy ground. 

 The time and duration of the period of flight varies. L. gibbosa appears 

 early in spring and is present throughout the summer. L. arcuata 

 and L. fusca disappear late in Jime, and after the beginning of July, 

 very few individuals of any species are foimd. In southern Indiana 

 and further south, L. ephilida, L. burmeisteri, L. quercus, L. gracilis, 

 etc., are present from June until August. In Utah, Idaho and Montana, 

 L. dubia is most important, in South Dakota, L. vehemens, in north- 

 eastern Iowa, south-western Wisconsin, and north-western Illinois, 

 L. fusca, etc. 



The most serious outbreaks were those of 1912 and 1915. The 

 natural enemies appear to be increasing in numbers and may in future 

 control any serious outbreak. The most effective insect enemies of 

 the larvae are Tiphia spp. and Asilids. The hfe-history of two species 

 of Tiphia has been determined ; in both cases it lasts one year ; the 

 eggs are deposited on the surface of the host, the females being partheno- 

 genetic ; the winter is passed in the larval stage within the cocoon. 

 Elis 5-cincta is an important enemy in some districts. The life-cycle 

 occupies a year ; it is not parthenogenetic, and differs from Tiphia in 

 that it paralyses the host completely during the act of oviposition. 

 Three Tachinids parasitic on the larvae are Microphthalma disjuncta 

 in the central States, M. pruinosa in New England, and Ptilodexia 

 tibialis in Texas. The Asilid, Promachus vertebratus, has been reared 

 from larvae feeding on white grubs, and is common in some parts of 

 Wisconsin. P. fitchii occurs in the eastern states and both this and 

 the preceding species have a three-year hfe-cycle. Predaceous 

 Carabid beetles and their larvae are important as a controlling factor. 

 Other enemies of minor importance are the Pelecinid, Pelecinus poly- 

 turator, the Ichneiunon, Ophion bifoveolatum, and the Bombyliid Fly, 

 Sparnopoliusfulvus. The following Dipterous parasites have been reared 

 from the adult : — Pyrgota undata, P.valida, Cryptomeigenia theutis, Eurixa 

 exile and Biomyia lachnosternae. Miscellaneous enemies include spiders 



