THE MICBOSCOPE. 95 



Ground Glass, for bringing out with good definition 

 Foraminifera, etc. For transmitted light. 



Opal or Porcelain, or even C/wia, for viewing dark objects 

 as opaque, such as Seeds, etc. For reflected light. 



Glass Slips, dull-varnished on one side, useful for most 

 opaque objects. For reflected light. 



These should be slipped under the slide on the stage of the 

 microscope, and may be procured at a very trifling cost. 



E. LOVETT. 



Proboscis of Tortoise Tick.— I cannot make out any terminal 

 opening. Mr. West's account of the channel for suction may be 

 right, but it cannot be made out by examination of a mounted 

 specimen; and certainly if the membrane described were "elastic," 

 it would prevent the passage of juices, by being drawn into the 

 channels. This remark of Mr. West's puzzles me. What proof is 

 there of its elasticity? and what is the supposed need of elasticity in 

 relation to it ? The central support could not prevent the 

 membrane falling into the two channels thus formed. I suppose 

 we must conclude that the elasticity of the membrane and the 

 power of suction are invariably well balanced ; but is it elastic ? 

 and why ? D. Moore. 



Eg^gs of Louse of Vieillot's Pheasant differ from those of 

 Reeve's Pheasant in having much coarser reticulations ; the general 

 shape is the same ; the thread attached to the lid is present, and 

 when absent it is probably accidentally removed. It is a very 

 common appendage to louse-eggs, and it occurs in 6 or 7 out 

 of 8 different species that I have. Are these egg-shells chitinous ? 



D. Moore. 



Mr. West's reply to the foregoing notes : — 



Dr. Moore's remark on the thread attached to the lid of the 

 Louse's Egg is highly interesting. This is a subject well worthy of 

 study. I believe there is no publication on them as a class yet, 

 and they would form excellent material for our " Proceedings," 

 stimulating intelligent inquiry into the subject as well. 



If these egg-shells in question be not chitinous, of what 

 material are they composed ? Simply animal membrane ? Some 

 appear from their porcellaneous lustre and brittleness, as if they 

 might be impregnated with earthy salts, — Carbonate and Phosphate 

 of Lime probably. 



The Larvae of Bird-Lice push off the cover of the beautiful 

 " urns " in which the first stage of their existence is passed, when 



