I've never had success in getting either curl
or wget
to download files which are being served from an Apache server where indexing directories
is enabled. I'm thinking this is your problem as well. The directories show up like this when you browse them:

In Apache they're enabled like this for example:
<Directory /var/www/domain.com/pdfs>
Options Indexes FollowSymLinks
</Directory>
Using the shell you're options are limited to getting the list of files and then downloading them one at a time using a command like this one:
% URL="http://www.lamolabs.org/blog/wp-content/uploads/2012/10/"
% curl -s $URL | \
grep "href" | \
grep -v "C=D;O=A" | \
sed "s#^.*href=\"#$URL#" | \
sed 's/">.*$//' | \
xargs wget
Breaking this down:
- URL="..." - is the URL I want to download files from
- curl -s $URL - get's the contents of the index.html generated by Apache
- grep "href" - get lines that contain only href
- grep -v "C=D;O=A" - eliminate the header bar line generated by Apache
- sed "s#^.*href=\"#$URL#" - replace .*href=" lines with URL
- sed 's/">.*$//' - remove trailing characters >.*$
- xargs wget - download each file using wget
You can run this as a single command:
url="http://www.lamolabs.org/blog/wp-content/uploads/2012/10/"; curl -s $url | grep "href" | grep -v "C=D;O=A" | sed "s#^.*href=\"#$url#" | sed 's/">.*$//' | xargs wget
Running it results in the following files getting downloaded:
% ls -l
total 1652
-rw-rw-r-- 1 saml saml 1351400 Oct 8 23:35 Anatomy-of-the-Linux-file-system.mht
-rw-rw-r-- 1 saml saml 485 Oct 11 00:42 eratosthenes_prime_sieve.pl_.txt
-rw-rw-r-- 1 saml saml 27191 Oct 3 21:42 Selection_005-150x150.png
-rw-rw-r-- 1 saml saml 24202 Oct 3 21:42 Selection_005.png
-rw-rw-r-- 1 saml saml 27141 Oct 3 21:42 Selection_006-150x150.png
-rw-rw-r-- 1 saml saml 24906 Oct 3 21:42 Selection_006.png
-rw-rw-r-- 1 saml saml 25783 Oct 3 22:17 Selection_007-150x150.png
-rw-rw-r-- 1 saml saml 111915 Oct 3 22:17 Selection_007-650x180.png
-rw-rw-r-- 1 saml saml 48109 Oct 4 09:57 Selection_007-e1349359020755.png
-rw-rw-r-- 1 saml saml 29336 Oct 3 22:17 Selection_007.png