Keywords: Gill slits.png The presence of gill slits in blue in an acorn worm left and tunicate right Originally uploaded to the English language Wikipedia by Zebra element http //en wikipedia org/w/index php title Special Log page File Gill_slits png file log 18 33 16 May 2010 UTC Own by Zebra element talk Faringotrema PNG Zebra element May 2010 Developmental biology Chordata |