Worm Breeder's Gazette 1(1): 4

These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.

A Simple Device for Counting Worms

S. Ward, R. Schubarth

Figure 1

In genetic crosses and in experiments measuring the number of 
progeny produced by a worm, the counting of progeny is tedious.  It is 
often important to kill off or remove all of one generation before 
they reach maturity in order to prevent a second generation from 
confusing results.  We have found that a miniature soldering iron can 
be used for killing individual animals on a petri plate.  The killing 
is reliable and fast if the tip is cleaned of roasted worm 
periodically.  If the soldering iron is connected to a counting 
circuit, such as those used in resistance type bacterial plaque 
counters, the counts are recorded automatically.  The schematic of a 
simple counting circuit we have built is diagrammed below.  The second 
terminal is connected to the agar surface by an alligator clip.  The 
standard copper tip on the iron can be sharpened for use, but we find 
it more convenient to use the fine pointed tip of a dissecting needle 
fastened to the soldering iron with a brass sleeve.  The whole system 
can be purchased and assembled for about $60.
[See Figure 1]

Figure 1