Ok! It works! Using my $counter in line 16 but nowhere else did the trick. In previous versions I had used 'my' with every instance of $counter.
I was asked to post the whole code, so, even though the problem is resolved, I will - the working version. :-)

Many thanks to all who responded - especially to sgifford whose working sample 'gave me a clue'. 

#!/usr/bin/perl -w
 
#   tcimage.pl
# by: Chris Cantrall
# on: 2003 May 12
# syntax: perl tcimage.pl *.jpg > photos.html
 
# create web page from list of images provided on command line
#
# WARNING: no checking of any kind is performed on input. Caveat usor.
 
use strict;
# get list of filenames from command line arguments
my @filenames = @ARGV;
 
my $counter = 0;
# add thumbnail image and link text to each filename
foreach my $name (@filenames) {
  if ($counter % 2){    #odd rows
    $name = qq{<tr><td><img align="center" valign="center" src="TN/tn_
+$name" width="75" height="42">
    &nbsp;&nbsp;<a href="$name">$name</a></td>\n};
  }else{                        #even rows
    $name = qq{<td><img align="center" valign="center" src="TN/tn_$nam
+e" width="75" height="42">
    &nbsp;&nbsp;<a href="$name">$name</a></td></tr>\n};
  }
  $counter++;
}
 
# create overhead for HTML page
my $header = qq{<html>
<head>
<title>Images of the Prime Focus Camera Shutter Controller</title>
</head>
 
<body>
<h3>Photos of the Shutter Controller</h3>
<table border="1">
};
 
my $footer = qq{
</ul>
</body>
</html>
};
 
# create output array
my @output = ($header, @filenames, $footer);
 
# output to screen or piped to file
print @output;

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In reply to Re: Error msg "requires explicit package name" by Theo
in thread Error msg "requires explicit package name" by Theo

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