Tes*ta"ceous (?), a. [L. testaceus, fr. testa a shell. See Testa.] 1. Of or pertaining to shells; consisted of a hard shell, or having a hard shell.

2. (Bot. & Zoöl.) Having a dull red brick color or a brownish yellow color.

Testaceous animals(Zoöl.), animals having a firm, calcareous shell, as oysters and clams, thus distinguished from crustaceous animals, whose shells are more thin and soft, and consist of several joints, or articulations, as lobsters and crabs.

Tes*ta"ceous (?), a. [L. testaceus, fr. testa a shell. See Testa.] 1. Of or pertaining to shells; consisted of a hard shell, or having a hard shell.

2. (Bot. & Zoöl.) Having a dull red brick color or a brownish yellow color.

Testaceous animals(Zoöl.), animals having a firm, calcareous shell, as oysters and clams, thus distinguished from crustaceous animals, whose shells are more thin and soft, and consist of several joints, or articulations, as lobsters and crabs.