12/31/98

I would like to know if there is any new technique about SEM and beetles,

what is the best way to mount the beetle.

Keep care and be of good cheer.

Regards

Vratislav Richard Eugene Maria John Baptiste

of Bejsak (Bayshark)-Collorado-Mansfeld

Coleoptera - Australia, Tenebrionidae of World

(incl. Lagriinae, Alleculinae)

Temporally home address:

32 Girrawheen Ave.

Kiama NSW 2533

Australia

e-mail: vratislav@bigfoot.com

ricardo@ans.com.au

(before Ricardo@compuserve.com

and ricardo@login.cz )

http://www.coleoptera.org

phone : 0414 540 465 (Australia)

+61 414 540 465 (International)

I dont know if this technique is the best but it certainly works for us.

Depending on what part of the beetle you want to examine, we stick and glue

with silver dag, an entomological pin (for the small beetles) or a normal

pin (for larger specimens)to an area of the specimen which is not going to

be observed. From here we place the specimen and pin in a stub like vice.

This allows you to gold coat the beetle and place in the SEM chamber with

minimal handling.

Ok yes the pin can be seen under the SEM. The idea is the mount the

specimen in such away that the pin will not obscure in anyway the views

that are wanted. ie if dorsal and front view are wanted then the pin would

be placed in the ventral side at an angle less than 90 degrees sloping

backwards towards the posterior end. This will give a greater angle to work

with when observing the frontal position.

I know this is a brief explanation, however if you want to ask any

questions please ring me on 02 9320 6198

Hope this helps

Sue Lindsay

SEM Lab Australian Museum

suelind@amsg.austmus.gov.au

Paint the pin with dag before mounting and if you get your contrast

right the pin dissapear into the bagground!!!

Just a usefull hint.

Mr. S H Coetzee Tell: (011) 716 2419

Electron Microscope Unit Fax: (011) 339 3407

Private bag X3 E-mail: Stephan@gecko.biol.wits.ac.za

Wits

Johannesburg

2050

Dear fellow microscopists,

I am a vendor, and we developed and sell "Entomounts", which are

basically specimen mounts with the entomology pins already in them. They

are provided as a convenience, and are so reasonably priced that I don't

care much one way or the other whether we sell a bunch of them or not

<grin>.

Happy New Year!

Steven Slap

********************************

Energy Beam Sciences, Inc.

The Laboratory Microwave Company

http://www.ebsciences.com

I've been using a variation of the "ento pin" for years that

provides a little more flexibility than a rigid pin. Cut a long,

thin triangular piece of thick aluminum foil (like that in a

weighing dish - in a pinch you can use aluminum or copper tape),

bend the base at a 90 degree angle, and stick it to the stub with

carbon paint or your favorite conductive adhesive. Mount the insect

on the point with conductive adhesive and coat. After coating, re-paint

the stub surface and pin with carbon paint to darken the background.

The mount is flexible enough to make fine adjustments to the positioning

of the insect (to get an exactly lateral view, or to hide the pin or

whatever)

and can be bent 90 degrees in any direction to get dorsal, ventral or

other views. This works a lot better than trying to tilt the stage, as

in most

scopes you lose the ability to move in the X or Y direction at high

tilts. Plus

the background remains darker if you don't have to tilt.

Hope this helps

JME

James M. Ehrman

Digital Microscopy Facility

Mount Allison University

Sackville, NB E4L 1G7

CANADA

phone: 506-364-2519

fax: 506-364-2505

email: jehrman@mta.ca

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