LOCAL DISTRIBUTION OF INSECTS. 515 



minute beetles, and not a few Hymenoptera and 

 frequent them. Morasses also have their peculiar insects. 

 In these you will meet with some of the scarcer Eutre- 

 china ; as Chl&nia holosericea and nigricornis, Blethisa 

 multipunctata, various Bembidia, &c. In this kind of dis- 

 trict in the ]sle of Ely Aphodius plagiatus has been taken, 

 and that scarce and beautiful butterfly Lyctena Virgau- 

 rea. Where land is cultivated the Entomologist as 

 well as the farmer may expect a harvest. Insects in 

 general are fond of perching on the summit of a blade of 

 grass or corn; and many minute ones may be taken 

 coursing about in the ears of the latter : some to devour 

 ihefungilli that infest the grain, as Phalacrus corruscus 

 in Reticularia Segetum / others to attack the grain itself, 

 as Cecidomyia Tritici; others to destroy these destroyers, 

 as three little parasites belonging to the Chalcidites a . 

 But I have already mentioned most of those insects that 

 are to be expected in such situations 5 : I shall therefore 

 only further observe, that upon barley particularly you 

 will meet with the species of Latreille's genus Cephus. 



With respect to soils, those that are light appear to be 

 most prolific in insects. Warm sandy banks are fre- 

 quented by Cicindela campestris, Opatrum sabulosum, He- 

 lops quisquilius, &c. : in them (when of a southern aspect) 

 Ammophilce.) Pompili 9 and numerous Hymenoptera nidifi- 

 cate. Chalk also attracts various insects. Latreille ob- 

 serves, that the Licini, Papilio Cleopatra, several species 

 afDasytcs, and some Lamice, delight in this kind of soil c : 

 in my own neighbourhood I have observed Polyom- 

 matus Cory don principally in chalk-pits. One of these 



a Linn. Trans, iv. 30. v. 96. t. iv. b VOL. I. LETTER VI. 

 * Geograph. &c. 6. 



2 L 2 



