piceous

1. (obsolete, rare) Of or pertaining to pitch (“a sticky, dark brown substance obtained from distilling turpentine or wood tar, or crude oil or tar”); having a quality like pitch.Examples: "I do not therefore require of you to believe, that the ancient rocks and compact bodies were diſſolved, but that many new ones were formed by the deluge, which had incloſed the ſpoils of the ſea within them. […] What other rational account will you give of that ſhell of a nautilus, which was found buried in a ſtratum of a piceous ſubstance below the bed of the river Arbis, where Artaxerxes commanded a bridge to be built over it?"Synonyms: pitchlike, pitchyobsoleterare

2. (chiefly entomology) Resembling pitch in colour; a very dark brown.Examples: "Piciroſtris. Oblong, black: ſilvery-ſilky: ſnout half way and legs piceous."; "The colour of the upper part is a mixture of yellowish-white and piceous disposed in dots, exactly resembling mosaic work, […]"; "Abdomen with shining cinereous tomentum, and with five lines of piceous spots; […] Tibiæ piceous towards the tips; tarsi piceous."