Transverse axis ( Henle, 1855 ) : The axis orthogonal to the longitudinal axis (Barclay, 1803) or rostrocaudal axis of the body in all animals with a nervous system (Monro, 1783); term introduced by Henle (1855, p. 1). In animals with radial symmetry it is the only axis orthogonal to the longitudinal axis (Barclay, 1803); in animals with bilateral symmetry it is divided into a dorsoventral axis and an orthogonal mediolateral axis with right and left halves; see Kuhlenbeck (1973, p. 112).