122 THE entomologist's RKt'ORD. 



enjoying the sunshine, flying over the water, and several times we dis- 

 tinctly saw them make a rapid descent and plunge their bodies into the 

 stream. We were close enough to see the process quite clearly. The 

 heat was very great and it was evidently a pleasure, and possibly a relief 

 to them, to come in contact with the cool water. — G. T. B.-B. 



^OTES ON COLLECTING, Etc. 



Note on the abundance of Biston hirtaria in 1912, and on 

 Insect Periodicity. — On April 6th 1 paid a visit to some friends near 

 Leytonstone, where I found B. hirtaria in extraordinary abundance. 

 In two roads which I visited, each about half a mile long, the front 

 gardens on both sides were lined with lime trees, and each tree had its 

 moths, some from 20 to 30, and on one side of a six inch diameter 

 trunk I counted 70 specimens. 



My friend tells me the caterpillars were a perfect pest last year, the 

 paths being covered with their trodden remains. The moths varied 

 from pale fawn to very dark brown, and grey, and quite a number were 

 as large as those illustrated on the frontispiece plate in Series 2 of 

 South's British Moths. Having no pillboxes I endeavoured to bring 

 some of the best forms home in a large cardboard box, the only avail- 

 able receptacle. Unfortunately one of the females had the audacity 

 to start laying her ova under the wings of another inmate, which 

 resulted in a general scrimmage. On reaching home I set a number 

 of the males free to the evident delight of the local sparrows, who 

 soon made short work of them, catching them as they flew. I put 

 some of the less lively males on an oak trunk in my garden, and some 

 females on lime trunks. On visiting the trees next morning I found 

 that two males had been seized bj' spiders and dragged into their 

 snares in holes in the bark. The females were still in the same 

 position seven days afterwards, having in the meantime laid their green 

 ova in chinks in the bark. I may mention that a female laid in a 

 a pillbox a batch of cream-coloured ova. 



What is the cause of this periodical abundance of a species ? One 

 season it is Phalera hiicephala that infests lime trees, rose bushes in 

 gardens, and anything else it can feed on, in districts as far apart as 

 Dulwich and Dartford, another season MalacosoHia {Boinhi/.v) nrnstria 

 devastates the fruit trees on the South Const, when bracelets of ova 

 can be found by the score on a small bush, another year Porthesia 

 rhrysorrhoea is stripping the hawthorn hedges on the South-East Coast, 

 or else its place is taken by one of the small ermine moth larvffi which 

 cover the hedges with their webs in every direction. Larvae of B. 

 hirtaria were also plentiful in North Kent and East Dulwich last year, 

 but the emergence in the latter place has only been normal. 



It is quite evident that the fine weather last Spring and early 

 Summer suited the larvse, and that the warm wet winter has favoured 

 the emergence of the imagines, but one is tempted to ask why we 

 did not get an abundance of /'. huccjthala larvse as well, which also 

 feed on lime trees. — C. W. Colthriip, 141, East Dulwich Grove, S.E. 

 April 15th, 1912. 



NoTF, ON THE EARLY Skason. — I have just found (April 16th), at 

 Margate, two full fed Abraj-as (/mssidariata larva?, spinning up for 

 pupation, and three others practically full fed on Emtniinnis. I also 



