Monthly Microscopical"! 
Journal, June 1, lsi69. J 
Transactions, dtc. 
333 
Little or nothing appears to have been done until about the 
time of the improvement of the microscope by the introduction of 
the achromatic principle; and preparations in balsam, similar to 
those to be found in every cabinet, seemed to have furnished the 
authority for all the representations down to the present time. 
The lithograph by Mr. Leonard, after specimens prepared by Mr. 
Topping, is the earliest and the best of these. There is no date 
upon the plate ; but it was probably published about twenty-five or 
thirty years ago. It has been followed by Dr. Carpenter in the 
various editions of ' The Microscope and its Kevelations,' and by 
other writers. A somewhat similar but far less accurate figure is 
given by Mr. Samuelson.* There is also a woodcut by Mr. G. W. 
Kufile, from the common preparation, in ' Science Gossip,' vol. ii., 
p. 83. 
These figures call for very few remarks. They differ chiefly in 
quality of execution ; being all more or less correct representations of 
the balsam-mounted and much-compressed proboscis so well known 
in every collection of objects. I have no fault to find with the pre- 
paration as a specimen of the mounter's skill. It is undoubtedly a 
great feat to reduce to an almost perfect plane an organ so thick 
and full of muscle, and having a complicated endo and exo skeleton 
of chitine. The object is one of singular beauty, is a valuable test 
for the performance of low-power objectives, and will probably 
always be one of the most saleable of preparations. 
The late Eichard Beck appears to have had his attention 
attracted by the imperfect state of our knowledge of the structure 
of the proboscis ; and from what I could gather from a conversation 
with him, he had devoted much time to inquiries connected with 
the subject, especially to observations upon the living insect by the 
aid of reflected light and the binocular microscope, a course of pro- 
ceeding strongly advocated and most successfully carried out by 
him, and to aid which he contrived many ingenious and extremely 
useful instrumental appliances. During the progress of the present 
inquiry I endeavoured to ascertain whether any of his valuable 
observations had been recorded ; but the only document existing 
was a water-colour drawing of the half-closed lips, dated 12th 
July, 1862. A half-obliterated pencil sketch is on the margin, 
which appears to represent a section of one of the pseudo-tracheal 
tubes. 
My own researches originated in an attempt to imitate the 
common preparation : considering glycerine a more eligible medium 
than Canada balsam, I endeavoured to mount a slide, and, finding a 
difficulty in flattening the proboscis, contented myself with allowing 
it to take its own position, which is represented in Plate XIII., and 
* * The Earthworm and the Common House-fly.' By James Samuelson and 
J. Braxton Hicks. 1858. 
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