Wednesday
May182016

Nuthatch

A dead nuthatch (Sitta europaea).

Found on the stairs of our block of flats on 2016-05-18.  It must have come in through the window and not been able to find its way out again.  Last year I saw them quite frequently in the trees around our flats.  This is the first I have seen this year.

Saturday
Mar192016

How to Reverse the Page Order in a PDF File

If someone scans the pages of a document in the wrong order then the resulting PDF file will have its pages in reverse order. On Linux this is very easy to fix. First install pdftk (if necessary):

  sudo apt-get install pdftk

Then enter:

  pdftk file1.pdf cat end-1 output file2.pdf

where file1.pdf is the name of your input file and file2.pdf the name of the ouput file.

(Thanks to emilien at Stack Overflow)

Tuesday
Jan192016

Black Muscid flies

For the past few months I have been using Fonseca's key (Handbook for the Identification of British Insects - Diptera Cyclorrhapha Calyptrata Section (b) Muscidae by E. C. M d'Assis Fonseca, 1968) to identify Muscid flies I have collected.  I was having trouble with some small black female flies which kept running to Dialytina atriceps (=Phaonia atriceps) but which definitely had only 2 posterior bristles on their mid tibae instead of the required 3. Well I think I have just solved the problem: they are Phaonia halterata. Instead of keying out before you enter the main Phaonia subkey they run right to the last couplet of the that subkey.  I now have to go back and recheck all the 20 flies I have already assigned to atriceps.  Using keys takes quite a lot of gettting used to.

Saturday
Nov212015

Butterfly

A comma butterfly, Polygonia c-album (Lepidoptera, Nymphalidae).  A bit late in the year for a butterfly but it has been a fairly warm autumn so far.

Photo taken in the field below Chazey Wood, near Caversham, UK, on 2015-11-15.

Saturday
Nov072015

Puffball Fungus

A puffball fungus, probably Lycoperdon perlatum.

Photo taken in Whiteknights Park, Reading, UK on 2015-10-31.