LEPIDOPTERA IN RELATION TO FLOWERS. 361 



wings, can only be placed second to the Bees in the constancy of 

 their affections for flowers. Plusia gamma, Linn., flies both by 

 day and in the evening, and Plusia iota, Linn., shows itself less 

 frequently in the sunshine, and the other species are evening fliers 

 only. The Plusias differ from most other Noctuse in that they often 

 sip nectar while hovering on the wing, never remaining long at one 

 flower. If they do settle, they are ready to start off on the least 

 motion of the observer. The plants which I have found most 

 attractive to Moths are : — 



Wild Flowers. — Lychnis diic^^na, Sibth. ; L. Flos-cuculi, Linn. ; 

 L. vespertina, Sibth. ; Anthyllis Yulneraria, Linn. ; Rubus (sp. T) ; 

 Potentilla Comarum, Nestl. ; Hedera Helix, Linn. ; Samhucus 

 nigra, Linn. ; Lonicera Periclymenum, Linn. ; Scabiosa Succisa, 

 Linn. ; Senecio Jacobcea, Linn. ; Cnicus arvensis, Hoffm. ; Cen- 

 taur ea nig7'a, Linn. ; Thymus Seiyylhim, Fr. ; (?) Urtica dioica, 

 Linn. ; Salix. 



Garden Flowers. — Viola, Trop^olum, Sweet William. 



Of these flowers tw^o are green, tw^o white, five yellow (includ- 

 ing Sallow), seven red or purple, and two blue ; and the forms of 

 the flowers are as variable as their colours, ranging from very 

 highly-specialised, long-tubed forms, like Lychnis and Lonicera, to 

 the very shallow cups of the Ivy. The Ivy, Ragwort, Sallow, and 

 Sw^eet William probably attract more species and greater numbers 

 than all the others put together. 



Flowers which open in the evening are usually white, or, at 

 any rate, very pale in colour ; and from this fact some have argued 

 that w^hite being so conspicuous in the dark, these flowers have 

 developed it in order that insects might perceive them the more 

 readily. Conspicuousness, however, instead of attracting, may 

 repel dark-coloured insects, such as are the majority of the night- 

 flying Moths. When a lepidopterist goes out "sugaring," he 

 takes very good care not to spread his mixture on the side of the 

 tree which is towards the light, knowing that if he did so he 

 would not see an insect. Moreover, all night-flowering plants, in 

 addition to a copious supply of nectar, are possessed of a singu- 

 larly sweet and agreeable aroma. May this superabundance of 

 sweets not counteract a weakness — their conspicuousness 1 



Let us take the tw^o plants which stand first on the list — Lychnis 

 diurna, Sibth., and Lychnis Flos-cuculi, Linn., and compare them 



