B>| 



REPORT OF THE DIRECTOR I919 79 



Richter, R. & E. Der Proetiden-Zweig Astycoryphe-Tropidocoryphe- 



Pteroparia. Senckenhergiana, I : i. 1919 

 Richter, R. Vom Ban und Lebcn dcr Tri!ol)iten. i. Das Schwiinmen. 



Senckenhergiana, Bd. i. 1919, p. 213 



4 On Color Bands in Orthoceras 



Color markings on the shells of fossil mollusks and brachiopods 

 have attracted the attention of authors from the early days of pal- 

 eontologic investigation. 



The American, and some European, publications describing color 

 markings in Paleozoic fossils have been lately listed by Roundy 

 (1914, p. 449); the European ones by R. Richter (1919, p. 94).^ 

 We see from these lists that zigzag color markings on a Carbonifer- 

 ous Pleurotomaria were described as early as 1836 by Philips in 

 his Illustrations of the Geology of Yorkshire, and colored Terebra- 

 tulas of the Triassic in 1845 by v. -Alberti in Germany. Since that 

 time a large number of cases of color markings have been described, 

 especially of gastropods and brachiopods, and a large proportion of 

 these from Paleozoic beds. 



The oldest case on record of color marking seems to be that of 

 the Holopea harpa from the Chazy of Valcour Island, 

 N. Y., described by Raymond (1906, p. loi). 



While most authors have simply described the color markings as 

 fascinating traces of the original wealth of beauty and color of the 

 shells that has been lost to us through their bleaching, some of the 

 more recent publications, notably those of Kayser (1871), Steinman 

 (1899), Deecke (1917), Oppenheim (1918) and Richter (1919), 

 deal with the bearing of the mode of sedimentation afid other factors 

 on the retention of color markings, on possible conclusions from the 

 coloring upon the facies and the origin of the coloring. Notice of 

 their conclusions will be taken in another place. 



We shall restrict ourselves here to the cases of color markings in 

 certain Ordovician cephalopods and make our specimens the subject 

 of a separate note mainly for the reason that their mode of colora- 

 tion seems to bear directly on the question of their mode of life. 



D'Archiac and Verneuil as long ago as 1842 described a specimen 

 of Orthoceras anguliferum from the Devonian at 

 Paf^rath, Germany, with " a beautiful chevron pattern." Marsh 

 records (1869, p. 326) that in 1865 he procured a second specimen 



' A complete list, including the numerous cases of mesozoic and tertiary 

 shells with color markings has been given by R. B. Newton in 1907, a large 

 list of color markings on fossil gastropods, brachiopods, pelecypods and one 

 cephalopod was given by Kayser (1871, p. 265). 



