A HISTORY OF SURREY 



pupx may be collected in an hour's time by sweeping the grass and low 

 herbage. 



The Ulopidce and Paropidce are only poorly represented in this 

 county. 



JASSID^E 

 Grass-jiies 



This sub-family, which is numerous in species and genera, includes 

 the insects commonly known as grass-flies. They affect all kinds of trees, 

 shrubs, herbs and gramineae. Though small, many are beautiful objects 

 under a microscope when viewed by reflected light. The pretty little 

 leaping Tettigonia viridit is very common in the Haslemere district, and 

 may be found coursing up and down the stems of coarse meadow- 

 grasses in midsummer. 



The "Jassidce are included in the Membraddce by Carolus Stal, but 

 it is not obvious why he thus located them. 



APHIDID^E 



Aphides Green-Jiies 



Comparatively few realize the fact that the larger part of the 

 animal matter in the world is the result of insect agency. Except 

 through the medium of foes and parasites the balance between vegetable 

 and animal life would not be maintained. Blight and insect-pest would 

 render useless all the efforts of the agriculturist. 



The wonderful multiplication of aphides, made possible by the 

 process of parthenogenesis and their spread through the dimorphism of 

 both sexes, is familiar to us. Thus under suitable conditions clouds of 

 these insects may appear within a few days in localities where they were 

 before only known as units. 



Crops. The agriculturist has perhaps no greater aphis-foes to 

 contend with than Siphonophora granaria, S. pisi, Rbopalosiphum rapce and 

 Aphis rumicis. The first-named species deposits its ova on the flower- 

 stalks of wheat and other corn-crops, and often destroys the produce of 

 many acres in a few days. There may be as many aphides on one corn- 

 head as there are grains of seed, which last become shrivelled and diseased 

 from their attacks. Fortunately more than half of these aphides will be 

 found stung or pierced by one of several kinds of ichneumon flies, but 

 this check mostly comes too late to save the character of the crop. 

 Siphonophora fist, known to farmers as the green dolphin, attacks legu- 

 minous plants and particularly the field pea. It is more common in some 

 seasons than others, and the companies are mixed with other allied species. 

 Aphis -uiciee often crowds the stalks of the wild vetch. Rbopalosipbum 

 rupee is almost omnivorous, and attacks indiscriminately the mangold, the 

 swede and turnip, the kohl-rabi and the potato. As injuring the last 

 plant it was named by Smee Aphis vasfator, and was thought by him to 

 cause the potato-rot. A . rumicis does great injury to the broad-bean, and 

 has the common name of the black dolphin. It may be known, as 



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