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A cephalopod Peismoceras Hyatt, 1884 from the Silurian (Gorstian) of Bohemia is the single known nautiloid genus of the suborder Barrandeocerina with a documented colour pattern. However, spiral bands on lateral side of the shell, oblique to the shell axis, illustrated by J. Barrande in 1865 in Peismoceras pulchrum and later mentioned in several papers are not typical for this species. Zigzag bands are more common and they are developed either on the entire circumference of the shell or on one lateral side, while the other side retained the above mentioned spiral bands. A marked asymmetry of colour pattern on lateral sides has been observed in several cases, but with no proven relationship to the slight dextral coiling of the shell. Densely spaced longitudinal bands preserved on ventral side of P. asperum (Barrande, 1865) are illustrated for the first time. Some unusual shell abnormalities occurring in Peismoceras are discussed. [ABSTRACT FROM AUTHOR]