Raymond — Trilobite Retaining Color-Markings. 461 



Akt. XXXVIII. — A Trilobite retaining Color-Markings; 

 by Percy E. Raymond. 



It lias often been questioned, whether trilobites shared 

 the brilliant coloring of some of the modern Crustacea, or 

 whether they in life exhibited the rather dull and drab 

 appearance which characterizes most of their fossil 

 remains. 



This problem still remains unsolved, but a small 

 pygidium which I collected from the Cambrian of Chero- 

 kee County, Alabama, in 1921, shows a distinct banding, 

 indicating that in some cases, at least, the body was not 

 of a uniform color. 



The pygidium mentioned is 9.5 mm. long and 16 mm. 

 broad, and lies upon the surface of one of the siliceous 

 fragments into which the shales of that locality weather. 

 The banding is not very conspicuous, in fact, the specimen 

 was examined several times before I became assured 

 that it was not of accidental origin. The surface is 

 covered by transverse stripes of light and dark gray, 

 the latter almost black. At the anterior margin is a 

 narrow light band, followed by the broadest one of all, 

 quite dark in tone. The two remaining pairs of dark 

 bands are much narrower, the last almost in line with a 

 continuation of the dorsal furrows. The first two pairs 

 cross the axial lobe, but as all turn backward they have a 

 somewhat radial effect. In addition to the bands, there 

 are many small, irregularly placed spots of a yellowish 

 hue. 



These markings probably do not retain the original 

 colors, which may well have been brilliant. It is interest- 

 ing to note that the pattern is such that the animal would 

 not easily have been detected if viewed from above were 

 the surface of the water gently agitated, and also suggests 

 patches or shadows of sea weeds. This trilobite seems 

 in fact to have been protectively colored, although it 

 lived at a time before the advent of jaw-bearing fishes 

 or cephalopods and could have had few if any active 

 enemies. The specimen is unique, not only as the only 

 trilobite yet found showing a color pattern, but also as 

 being the most ancient fossil so marked, the next oldest 



