PROCEEDINGS OF THE SOCIETY. 
255 
The President exhibited an improved form of his mechanical stage, 
and read a description of the alterations made and the advantages 
obtained thereby. (See p. 185.) 
Dr. Dallinger thought that the stage in its present form was to be 
highly commended, as it firmly clipped the object, and yet left it free 
for such manipulation as might be needed with homogeneous lenses, at 
the same time avoiding the possible danger to the mount that arose from 
the older over-arching spring. 
The President said, in answer to a question, that provision had been 
made for tightening up the bevelled gear by means of a capstan-headed 
screw provided for the purpose. 
Mr. F. Enock was then called upon by the President to describe an 
extremely interesting exhibition under twenty-six Microscopes in the 
room of examples of every known genus of the British Mymaridae. 
Mr. Enoch said he felt he ought at the outset to thank the Society 
for affording him this opportunity of exhibiting a complete collection of 
the Mymaridse. Of course he supposed that everyone there would know 
something about them ; but having overheard someone inquire what are 
the Mymaridee, perhaps it might be well just to mention that they 
are minute Hymenopterous insects, all of which are egg-parasites, 
depositing their own eggs inside the eggs of other insects. In size they 
are so small that they must all be treated as microscopical, the smallest 
exhibited that evening being only 1/85 in. long, and the largest not 
more than 1/50 in. Not very much had hitherto been known about 
them, and he might fairly say that the British Mymaridae would come 
under the head of neglected families. In 1797 Dr. Shaw exhibited an 
insect of this class, and made a drawing of it ; but he was not at all certain 
what it was. Very few drawings appeared to have been made of these 
minute creatures, and those which were preserved were, in some cases at 
least, such as to make recognition impossible. A. H. Haliday, however, 
established the family in 1883, but it was elaborated by Francis Walker 
in 1846. Some time ago he wanted to identify a specimen which was 
found by Sir John Lubbock in 1862, and named by him Polynema natcins ; 
and through the kindness of the Trustees of the Dublin Museum, Hali- 
day’s type collection of British Mymaridae was lent to him. He found this 
collection had been very much neglected as to its condition ; it consisted 
of 172 specimens gummed upon card — some very much gummed — but he 
had obtained permission to remount them where desirable, and had gone 
through the whole collection, making a separate drawing of each, and had 
found his examination of them to be a very interesting study. One genus, 
named by Haliday Panthus , had been suppressed by Walker, who con- 
sidered it to be identical with Haliday’s Anagrus. This, however, had 
proved to be not the case ; and by restoring this, Haliday’s collection was 
made up to eleven genera. Since he had given his attention to the 
matter — principally in 1885 — he had discovered eight new genera ; and 
he was sure that he should be able to find many more by devoting a 
little more time to the subject. All the species searched for the eggs of 
injurious insects, and he had watched them with great interest running 
about over the eggs, tapping each with their antennae, and if the egg was 
.all right, boring through it and then laying an egg, or sometimes two 
