26 INSECTS AND PLANTS AT PORTLAND. 



identified with certainty from any other part of the world, but 

 as the botanists have taken 60 years to decide that it is a 

 distinct species, and as it occurs here with a variable allied 

 species, L. binervosum, I feel that the next generation of 

 botanists may reverse this decision ! The other specially rare 

 plants given by Mr. Barrett are Polycarpon tetraphylhun, 

 Sedum rupestre, var. minus, Valerianella eriocarpa, V. dentata, 

 var. mixia, Hieracium platyphyllwn, and Muscari racemosum. 

 One or both of these species of Limonium forms the food plant 

 of a plume moth Agdistes bcnnctii which used to be common at 

 a spot at the end of this undercliff, but lower down by the sea 

 and reached by a very steep and somewhat perilous descent. 

 This is now, alas, destroyed, like the great Neolithic burial 

 ground, many dene-holes and other things of great interest, by 

 quarrying. But \vhen Mrs. Richardson and I used to spend about 

 two nights a week here, during the summer and autumn, collecting 

 moths, from 1886 to about 1900, this end of the undercliff was 

 comparatively untouched, and a splendid place for many rare 

 species. Here we first took Epischnia bankesidla, Richardson, 

 a species new to science in 1887; and at the bottom of this 

 perilous descent, six years afterwards, she discovered the larva 

 on that beautiful plant Inula crithnioides, Golden samphire, 

 common along the cliffs by the sea. In 1894 she also found two 

 larvae on this plant which produced the very rare Plusia ni. 

 They closely resembled the larvae of the very common Silver Y 

 moth (Plusia gamma), and I urged her not to keep them, but she 

 insisted, with this grand result ! At the same place occurred 

 Acidalia rusticata, a local species, and a relative of the well- 

 known Portland wave (Acidalia degenerarid), which is not 

 uncommon under the prison, and can be beaten out of bushes 

 in the day time, when it generally flies a little way and then 

 flops down on the ground with its wings spread. It occurs 

 nowhere else in England. . Tinea subtilella, a very small dark 

 cream-coloured moth, is also confined to Portland as far as 

 this country is concerned, and was discovered by Mrs. Richard- 

 son near here. We hunted in vain for the unknown larva, 

 much worse than a needle in a bundle of hay, as there was no 



