132 



THE YOUNG NATURALIST. 



[June 



which they refer, so that for instance in this case enquiries might be 

 made in the district from which Mr. Tugwell thinks our galii came, to 

 ascertain whether or not D. galii was unusually common there last 

 year, or whether it is double brooded there. It is as easy to say on 

 the unexpected appearance of an insect that it is blown over from 

 somewhere or other, as it is difficult to disprove or believe it. These 

 periodical appearances are in our present state of knowledge so 

 mysterious and so inexplicable, that to ascribe all to a vague " blown- 

 over " theory seems but a faint-hearted way of shelving a difficulty, 

 which should rather be approached in the careful and thoughtful 

 manner in which it was treated by Mr. W. E. Sharp, in the last 

 number of the Young Naturalist. 



53, Lincoln's Inn Fields, 25th May, 1889. 



Notes and Observations. 



Chrysis ignita. — " Will you kindly name the enclosed fly, I saw 

 several in July last resting on a sandbank, the colours were so beauti- 

 ful that I could not resist the temptation of boxing one. If of any 

 service to you, please retain it ? — W. U'Ran." 



The insect is Chrysis ignita, as you truly observe, it is a very lovely 

 insect, with its beautiful metallic colours, head and thorax blue-green, 

 often with a dash of gold ; the abdomen coppery-carmine. Curtis 

 says, " nothing can exceed the splendour and brilliancy of the Chrisi- 

 didce, which have been compared by Latreille to precious stones, and 

 very aptly called by Jurine the humming-birds of entomologists. It 

 must be confessed that nature has been lavish in adorning them with 

 such beautiful and effulgent colours, that our astonishment and 

 admiration are equally awakened on contemplating them. Latreille 

 supposes this splendour may dazzle their enemies and so facilitate 

 their escape." This insect varies much in size, varying from three 

 to seven lines in length, also in the metallic lustre of the colours. The 

 apical margin of the abdomen is terminated generally by four spikes, 

 some longer than others and sometimes almost wanting, the earlier 

 authors dividing them into species, according to the length and 

 arrangement of the spikes, consequently there are some half-dozen 

 names for this variable creature. When captured they roll themselves 

 into a ball ; the thorax and abdomen is wonderfully hard and it is 

 with great difficulty you can pass a pin through it. This insect is a 

 parasite on wasps and bees ; I have bred it from Odynenis pictns, the 



