CICADINA (cont.) 

 JASSIDAE 



Athysanus, Burm. 



communis, J. Sahl. 



sordidus, Ztt. 



obscurellus, Kbm. 



obsoletus, Kbm. 

 Deltocephalus, Burm. 



striifrons, Kbm. Falmouth 



pascuellus, Fall. 



distinguendus, Flor. 



socialis, Flor. Truro 



sabulicola, Curt. 



striatus, L. 



normani, Scott. 

 Allygus, Fieb. 



mixtus, Fabr. 

 Thamnotettix, Ztt. 



prasina, Fall. Par; Falmouth 



subfuscula, Fall. 



spendidula, Fabr. 



crocea, H. S. 



attenuata, Germ. 

 Limotettix, J. Sahl. 



striola, Fall. 



quadrinotata, Fabr. 



nigricornis, J. Sahl. Botut 



Fleming 



INSECTS 



CICADINA (coat.) 

 JASSIDAE (cont.) 



Cicadula, Fieb. 



sexnotata, Fall. 



TYPHLOCYBIDAB 



Alebra, Fieb. 



albostriella, Fall. 

 Kybos, Fieb. 



smaragdula, Fall. 

 Chlorita, Fieb. 



flavescens, Fabr. 



viridula, Fall. 

 Euptcryx, Curt. 



vittatus, L. 



urticea, Fabr. 



strachydearum, Hardy 



melissae, Curt. Scilfy (Dale) 



auratus, L. 



filicum, Newm. Mittook (Mrs. 



Clark) 



pulchellus, Fall. 

 Typhlocyba, Germ. 



sexpunctata, Fall. 



ulmi, L. 



tenerrima, H. S. 



aurovittata, Dougl. 



CICADINA (cont.) 

 TYPHLOCYBIDAE (cont.) 



Typhlocyba douglasi, Edw. 



rosae, L. 



quercus, Fabr. 



geometrica, Schr. 

 Zygina, Fieb. 



flammigera, Geoff. 



parvula, Boh. 



PSYLLINA 



PSYLLI DAE 



Psylla, F. Loew 



simulans, Forst. 



pyricola, Forst. 



peregrina, Forst 

 Arytaena, Scott 



genistae, Latr. Truro 



TRIOZIDAE 



Trioza, Forst. 



galli, Forst. 



urticae, L. 



crithmi, F. Loew 



albiventris, Forst. 



APHIDES 



The work of identifying the insect pests of the county at the Technical Schools has necessitated 

 a considerable amount of attention being given to the commoner aphides, and in 1901 and 1902 an 

 attempt was made to collect and identify every species observed in the county. The efforts in this 

 direction were not altogether successful, and it is probable that one or two of the species kept under 

 observation for some time are not described in Buckton's Monograph. The peculiarities of the 

 physiological processes involved make the study of the order very complicated, and the extensive 

 morphological differences among members of the same species greatly increase the difficulties of 

 identification. The parthenogenetic production of apterous young for few or many generations in suc- 

 cession, and for the most part of the female sex only ; the occasional appearance of winged individuals, 

 sometimes in considerable numbers ; the frequent remarkable disproportion in numbers between the 

 sexes when the males do appear ; the occurrence of viviparous and oviparous broods ; the difference 

 of sex organs in the same sex and species ; the extraordinary changes in life habits in successive 

 generations and the consequent formation of so-called parallel series, are all so many difficulties in 

 the way of accurate diagnosis. The following notes, however, deal only with those species about 

 the identification of which there is no reasonable doubt. 



Siphonophora rosae is, of course, ubiquitous. S. granaria in some years appears on wheat about 

 Launceston, but is much more troublesome locally on grass than on grain. In 1 90 1 S. phi did 

 considerable damage on garden peas about Bodmin. In 1902 almost every nettle in the neighbour- 

 hood of Truro carried a large colony of 5. urticae. S. dirhoda, S. lactucae, S. ruii, and S. rosarum 

 are at times abundant locally, while S. jaceae and S. sonchi are widely spread and common. S. scabiosae 

 has been found plentifully near Falmouth, and S. chelidonit in the neighbourhood of Truro on 

 bramble. S. alliariae was common in 1902 at Newquay on nipplewort. S. fragariae attacked the 

 strawberries about Truro, Falmouth, and Penzance in 1 900, and in places did considerable mischief. 

 S. hieracii and S. millefolii seem to be rather local. 5. circumflexa was found on Ixia sparaxis and 

 other Cape bulbs at Tresco, Scilly. S. pelargonli has been taken on various plants, but especially 

 on shrubby calceolarias, at Truro. S. carnosa was plentiful at St. Clement, Truro, in 1902 on 

 nettles, and appears to be widely spread. S. longipennis was fairly common in 1901 on Poa annua 

 close to the Falmouth Docks. S. convolvuli has been taken at Miramar, Truro, on periwinkle and 

 on various bindweeds. S. avellanae is widely distributed in the Truro district and elsewhere. 

 S. tanaceti has been obtained on tansy in the Looe valley, and on feverfew in gardens about Truro. 

 S. artemisiae occurs on mugwort about St. Ives. S. so/idaginis was common in 1902 on golden-rod 

 at Bishop's Wood, Truro, and on anthemis and groundsel at Millook. S. tusstlaginis is occasionally 



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