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afternoons seemed to catch the warmest rays of the sun. There 

 Pyrameis atalanta loved to sit with outspread wings. 



But the west wall and the shrubbery in front of it formed the spot 

 of which I really meant to speak. This shrubbery was somewhat 

 overgrown, and consisted mostly of hornbeam and lilac with a few 

 elders, Portugal laurel, and other shrubs. Nearly the whole of the 

 ground below the trees and bushes was over-run with ivy. The wall 

 was ivy-covered, and in the spring bore nests of thrush, blackbird, 

 and hedge-sparrow, but it was old, and many of the bricks, loosened by 

 the rains and chill nights of winter, had fallen and were lying on the 

 ground, partly hidden by the trailing ivy. Many of these bricks were 

 moss grown, showing the general humidity of the low-lying ground, 

 only separated from the Thames by the terrace to the south. Here, 

 on and under these mossy bricks, lying amid the ivy beneath the 

 trees, flourished, unknown to the world, the largest and most 

 prosperous community of Clausilia biplicata in the whole of the 

 British Isles. This shrubbery was bordered by the wall on the west 

 and a narrow gravel path on the east. The soil was a dark mould, 

 possibly overlying an alluvial bed. Above the ivy grew here and 

 there a few plants of Enchanter's nightshade, but not much else. 

 Above these rose straggling bits of elder and seedling sycamores. In 

 other spots the lilacs made a thick covert. If one threw a stone into 

 these bushes after dark in the May evenings, one would be answered 

 by the challenging notes of the greater whitethroat. Higher than the 

 lilacs the hollies reared their dark green foliage, and higher still rose 

 the hornbeams and sycamore trees, so that the home of Clausilia 

 biplicata was alike sheltered from the rough winds and heavy rains, 

 as well as from the scorching rays of the summer sun. Claiisilia 

 biplicata occurred chiefly on the fallen bricks, but could also be found 

 on the wall, and in the holes where trees had fallen and the stumps 

 rotted away, and sometimes in the vegetable rubbish below the ivy. 

 They were fond of getting the mouth and last whorl into a hole in 

 the bricks, and the young specimens were generally hidden in the 

 holes, sometimes in twos or threes. Besides shutting their doors or 

 clausilia, as I suppose they did do, they would often spin a slight 

 epiphragm over the mouth of the shell, which no doubt helped to fix 

 them to the moss or brick. They are hardy little creatures, as I have 

 found them crawling over the bricks when frost was on the ground. 

 They varied in numbers at different times, as most things do, but 

 were always plentiful. On the other side of the wall was a damp 

 field with a few willows. Here C. biplicata also occurred, but only 

 sparingly, at the foot of the willows and on a broken-down wall. 



In this field Arion ater. Helix arlmstorum, and Carychium 

 ??iinimtim might be found. The true home, however, of C. biplicata 

 was the shrubbery. With them on the underside of the bricks lived 

 Clausilia bidentata, Cochlicopa lubrica, Vallonia costata, Hygromia 

 hispida, H. riifescens, and, of course, Pyramidiila rotundata. Agrio- 

 liffiax agresiis, Vitrina pellucida, Vitrea crystallina, V. cellaria and 



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