geneous mixture as constituting his genus Bombyx, viz. cratcegi, 

 populi, castrensis, neustria, lanestris, trifolii, quercus, and rubi, besides 

 ten others that are not British ; in fact, the whole of our British 

 species fall into only two genera, those just mentioned in Bombyx, 

 and potatoria, quercifolia, and ilicifolia, with eleven species not 

 British in Lasiocampa. 



With Kirby's list * we obtained the first rational generic grouping 

 of the Lasiocampid moths. Here we see how truly it may be said 

 that our British species are to a great extent individuals of separate 

 well-marked and well-defined genera, each of which has its own 

 group of near allies, in some instances extending to several species. 

 Thus Trichiura contains — besides cratcegi — khasiana from the Khasia 

 Hills, aliaria from Pebas, obscura from Australia, and ? albiplaga 

 from the Cape. Pivcilocampa has — besides populi — subpurpurea from 

 Tokei, and habitus from Vera Cruz. CHsiocampa contains — besides 

 castrensis and neustria — testacea from Japan, itidica from the East 

 Indies, californica from California, fragilis from Nevada, constricta 

 from San Francisco, strigosa from Yosemite Valley, erosa from 

 Oregon, thoracica from California, incurva from Arizona, disstria and 

 americana from North America generally, and ? bilineata from 

 Senegambia. At the same time Kirby separates the European 

 species franconica, intermedia, and apicola (a/pico/a), and the Mon Pin 

 species flavomarginata, from CHsiocampa, under the name Mala- 

 cosotna, a separation that we think unnatural, and therefore un- 

 necessary. Gastropacha {Eutricha) contains — besides quercifolia — 

 populifolia from Central Europe, angustipennis from North China, 

 undulifera from North India, divaricata, sinuata, and torrida from 

 Darjiling, modulata from Bhamo, phidonia from Surinam, ? gerstceckeri 

 and knoblauchi from Chinchoxo. 



If only our British insects were looked at, one would say at once 

 that quercifolia and ilicifolia must fall into the same genus ; but no, 

 with the fauna of the world before us we find that ilicifolia is the 

 centre of its own group, the genus Phyllodesma (Epicnaplera), which 

 contains — besides ilicifolia — suberifolia from South-west Europe and 

 North Africa, americana from North America, ferrug'mea from 

 Michigan, californica, roseata, and alascensis from California, ? modesta 

 and thyatira from Panama, and tremulifolia from Central Europe. 



I have, I trust, quoted sufficient instances to bear out my point, 

 viz. that almost every individual species of our British Lasiocampids 

 is the representative of a special genus when we take into con- 

 sideration the faunas of the world. 



Rut not only are many of our British species representatives of 

 different genera, they are also isolated examples of different tribes. 

 No one, for example, comparing in all their stages say Trichiura 

 cratcegi with Lasiocampa quercus, and these again with Gastropacha 

 {Eutricha) quercifolia, could suppose for a moment that these 

 belonged to the same tribe ; whilst at the same time the comparison 



* " Catalogue of Lepidoptera Heterocera," Vol. I., 1892. 



