l8Gfi.) 177 



Para, Amazons (Bates & Wallace). Demerara (Piftard). 



The difference between our two species consists in the two short 

 streaks near the base of the hind-wing, on the under-side, being black 

 in Ep. Batesii, and rufous-brown in Ep. Ancea, and in the row of minute 

 ocelli of the same wing being surmounted in Ep. Batesii by detached 

 lunules, and in Ep. Ancea by a continuous streak. Tlie males differ a 

 little also in the shape of the blue belt, and, as I have said before, con- 

 siderably in that of the tawny-orange belt. 



It is not uncommon in the Order Lepidoptera to find perfectly dis- 

 tinct species distinguished from each other by such minute points of 

 difference as these separating our two Epicalice ; but it cannot be said 

 that full proof is afforded of their true distinction as species, until we 

 find that each kind has its own mate and maintains itself, from genera- 

 tion to generation, free from intermixture ■ndth its relative. Such results 

 as these show how important it is to study both sexes in investigating 

 species. There cannot be much doubt that the pairing together of 

 similar varieties, in the first stages of the segregation of new varieties, 

 and their refusal to intermarry with sister varieties or the type of their 

 species, have played a great part in the origin of new forms on our 

 earth. 



AN ESSAY TOWARDS A KNOWLEDGE OF BRITISH HOMOPTERA. 

 BY THE BEV. T. A. MARSHALL, M.A. 



{Continued from page 146.) 



b. Vertex antice obtusangulus vel rotundatus. Antennae fronti 



sequales longitudine vel parum longiores. 

 t Vertex pronoto non brevier. 



* Vertex antice obtusangulus. Alae completaa. Heme- 

 lytra ? abdomine longiora ; ^ transversim nigro-fasciata. 



3. — Acocephalus albifrons, Lin. 



Vertex longitudine vix dimidiae suse inter oculos latitudini aequalis, 

 medio vix cariuatus. Antennae fronte lougiores, articulo 2do nigro. 

 Alae completse. 



(^ . Pallide flavo-brunneus, colore plus minus saturate. Hemelytra 

 nigricantia, basi flavo-brunnea, fasciis duabus transversis (altera ante, 

 altera pone medium), interruptis, albidis; apice albido. Ad suturam 

 interdum, post fasciam 2dam, macula rotunda, communis, albida. Pedes 

 testacei, tibiis anticis apice, posticis fere totis, nigris. 



