548 PHYSIOLOGY. 



which, as larvae, live upon fruits. Among our fruits, the plum, apple, 

 and pear are attacked by a small moth, Tinea (Carpocapsa, Tr.) 

 pomona, and which, although it does not destroy the propagative powers 

 of the seed, yet it renders the fruit disagreeable to us. Thus another 

 caterpillar of a moth attacks the fruit of the chestnut (Castania vesca), 

 and destroys, by causing the fruit to fall before it is ripe, a rich and 

 profitable harvest. The date also is destroyed by a larva which 

 Haselquist observed, and refers it to the genus Dermesles, but certainly 

 incorrectly. Another larva of a moth, Pyralis fasciana, F., lives in 

 grapes, and destroys the most beautiful and largest grapes. But not 

 this only attacks the vine, but many other insects in different countries. 

 Pyralis vitana, F., as larvae, devour the leaves. In the Crimea, the 

 larva of a Zygoma attacks the young shoots as well as the larva of 

 Eumolpus Vitis, F., and of Rhynchites Bacchus, Herbst. In Silesia, 

 in the vicinity of Griinberg, where the vine is extensively cultivated, 

 Thylacites geminalus, Germ., is a destructive enemy to young shoots, 

 as it entirely consumes them immediately upon the budding. Lethrus 

 cephalotes does the same in Hungary. In southern countries where 

 the vine is cultivated, a species of Coccus sometimes destroys the entire 

 vintage by sucking the young shoots. A caterpillar also lives in the 

 fruit of the olive, which destroys the kernel -and produces Tinea 

 oleella, F. A second larva lives in the same plant, that of Oscinis 

 olece, Lat., an insect belonging to the family of the flies, whose nearest 

 ally, namely, Dacus Cesari, and the species of the genus Tephritis, 

 follow a similar mode of life. Tephr. cardui especially attacks thistles 

 and burdocks, and partly lives in the pith of the stem and partly in 

 the fruit and flower which it then distorts. Other dipterous maggots 

 distort plants by gall-shaped excrescences, for instance; the genera 

 Cecidomya, Lasioptera, &c. One of these maggots especially attacks 

 the ripening ears of corn, and thereby occasions great destruction. 

 Kirby has described this fly by the name of Tipiila tritici*. 



306. 



We will now drop the thread of our inquiry into those insects which 

 are injurious to plants or which restrict their superabundance, convinced 

 that the instances adduced above sufficiently prove a strong relation 

 between plants and insects. We must now prove, on the opposite side, 



* Lin. Trans., vol. iii. p. 243 245 ; vol. iv. p. 224239; ami vol. v. p. 9l 11<>. 



