94 INDIRECT INJURIES CAUSED BY INSECTS. 



appears to be a species of Holcus or Milium, is the appropriate food of 

 another species of Calandra 1 , which I found abundant in it. 



Rye, in this island, is an article of less importance than wheat ; but in 

 some parts of the Continent it forms a principal portion of the bread- 

 corn. Providence has also appointed the insect means of causing a scarcity 

 of this species of food. The fly before noticed (Oscinis pumilionis) intro- 

 duces its eggs into the heart of the shoots of rye, and occasions so many 

 to perish, that from eight to fourteen are lost in a square of two feet. 2 

 This fly, in 1839, did much damage to the rye at Grignon, in France 3 , and 

 in 1841 to that near Kingston, Surrey. 4 A small moth, also (Margarita 

 secalis), which eats the culm of this plant within the vagina, thus destroys 

 many ears. In common with wheat and barley, it also suffers from Leeu- 

 wenhoek's wolf and the weevil, when stored in granaries. 



Barley likewise, another of our most valuable grains, has several insect 

 foes, besides the beetle (Zabrus gibbus), already alluded to (p. 134.). The 

 gelatinous larva of a saw-fly (Tenthredo L.) preys upon the upper surface 

 of the leaves, and so occasions them to wither, Musca kordei of Bier- 

 kander also assails the plant. A tenth part of the produce of this grain, 

 Linne affirms, is annually destroyed in Sweden by another fly not yet 

 discovered in Britain (Oscinisfrit)^ which does the mischief by getting into 

 the ear; as does likewise O. lineata F. Dr. J. N. Sauter has described a 

 fly which he calls Tipula cerealis (most probably a species of Cecidomyia), 

 the larvae of which, eating the stem of barley and spelt (a kind of dwarf 

 wheat), did great injury to these crops in the grand duchy of Baden in 

 1813 and 1816 ; and the same, or an allied species, is supposed to have 

 formerly destroyed the oats in Styria and Carinthia. 5 A small species of 

 moth described by Reaumur, though not named by Linne, which may be 

 called Tinea hordei ( Ypsolophus granellus ?), devours the grain when laid up 

 in the granary. This fly deposits several eggs, perhaps twenty or thirty, 

 on a single grain ; but as one grain only is to be the portion of one larva, 

 they disperse when hatched, each selecting one for itself, which it enters 

 from without at a place more tender than the rest ; and this single grain 

 furnishes a sufficient supply of food to support the caterpillar till it is 

 ready to assume the pupa. Concealed within this contracted habitation, 

 the little animal does nothing that may betray it to the watchful eye of 

 man, not even ejecting its excrements from its habitation ; so that there 

 may be millions within a heap of corn, where you would not suspect there 

 was one. 6 



1 Circulio testaceus, Ent. Brit. 



2 Marsham in Linn. Trans, ii. 80. De Geer notices the injury done by this 

 fly to rye, and observes that before it had been attributed to frost, ii." 68. 



3 Ann. Ent. Soc. de France, viii. p. xiii. 



4 Proceed, of Ent. Soc. Land. Oct. 5. 1840. 



5 Kollar on Ins. inj. to Gardeners, &c. 124. 



6 Act. Stockh. 17oO, 128. Reaum. ii. 480, &c. Barley, like wheat, and indeed 

 all white corn, is much injured in the granaries of the corn-dealer by the larvae 

 of the little moth (Tinea granella L.), the wolf of Leeuwenhoek before referred to. 

 On visiting those of Messrs. Hellicar, Bristol, in October, 1837, with my friend, 

 W. JRaddon, Esq., we found the barley lying on the floors covered with a gauze- 

 like tissue formed of the fine silken threads spun by the larvae in traversing its 

 surface, on recently quitting it for the purpose of undergoing their metamorphosis 

 in the ceiling of "the granary, formed of the joists and wooden floor of the story 

 above. What was remarkable, as Mr. Raddon communicated to the EntomologicaV 



