Calumet Caltar Type Y 240mm f6.8 Lens Question

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220812421313&ssPageName=STRK:MEWNX:IT

I feel kind of bad/dumb asking this question, but can someone answer if this lens is suppose to have a rear element (that threads onto the back of the shutter)? I searched for images of this lens for hours, and its Rodenstock counterpart, but came up empty handed. I'd really appreciate your help. Thanks.

Mine has a very distinct rear cell that's easily visible at the angles of the pictures. I asked the seller about it and he replied that it did indeed have the rear cell, though it's certainly not shown in the photos. I've never been able to find much on the web about these, and the Vade Mecum doesn't list this focal length in its listing of Rodenstock's Ysarex lenses.