This bromalite gets its name from the Greek hira (gut or intestine), and the Greek bromus (food). It presents as an "elongate(d), convoluted, longitudinally-striated cylinder that tapers on both ends" and comprised of siderite.
Since body fossils (carcasses) are not present or otherwise associated with this type of specimen, there is some debate as to whether these are geological (pseudofossils) or cololites.
Reference: Hunt, A. P., Lucas, S. G. & Spielmann, J. A. (2012b): The bromalite collection at the National Museum of Natural History (Smithsonian Institution) with descriptions of new ichnotaxa and notes on other significant coprolite collections - New Mexico Museum of Natural History and Science, Bulletin, 57: 105-114.