CICADID^. 369 



References to Literature consulted. 



Board of Agriculture Leaflet, A ^ 



Edwards, Jarnes. The Hemiptera-Homoptera (Cicadina and Psyllina) of the 

 British Islands. 1896. 



Riley, C. V. Notes on North American Psyllidse. Proc. of Biol. Soc. of 

 Washington. 1884. 



Witlaczil, Dr Emanuel. Die Anatomie der Psylliden. Wien. 1884. 



Part II. 



CICADID.E. 



This family of insects is generally overlooked by the practical man, 

 inasmuch as he groups them along with the Aphidida? or " Green-fly." 



The injuries are not so conspicuous as to arrest special notice. In 

 fact, the injuries done by these creatures are of such a nature as to 

 suggest asking the question, What is damage 1 As regards the damage 

 actually done, three very general examples may be given the first 

 from the nursery, the second from the garden or orchard, and the third 

 in the meadow. With regard to the example from the nursery, a 

 walk alongside a plot of wych-elms, say from 3 to 5 ft. high, in 

 August or September, coupled with a little observation, will show that 

 the foliage has entirely lost its green hue, and is of a sulphury-yellow 

 colour. If the leaves are slightly shaken, a shower of tiny active 

 insects of a yellow colour, harmonising with the foliage, will dance 

 about in all directions. These are known as TyjpMocyba ulmi, and 

 may be taken as the most injurious of forest Cicadidse. A similar 

 example on pear-trees, more especially those on walls, will suffice for 

 those in the orchard ; and as regards those in the meadows, the most 

 common example is that of the " cuckoo-spit " that froth-like spittle 

 substance which harbours the larva of a common example of a Cicadid. 



Many varieties of deciduous trees harbour their own special species 

 of Typhlocyba, and some of them are very beautifully marked, and 

 would therefore form an interesting collection ; but the following very 



2 a 



