Thymus humifusus Bernh. ex Rchb. is mentioned as a new species for the Netherlands flora; it was found near Gulpen (prov. Limburg). Moreover the putative hybrid Th. humifusus X Th. pulegioides (Th. X schulzei Ronn. ex Machule) was found there. Th. humifusus may be distinguished from the two other Netherlands species, viz. Th. pulegioides and Th. serpyllum as follows: 1. Flowering stems distinctly angled, hairy on the angles only; plants mostly more or less ascending; leaves rather thin Th. pulegioides L. 1’. Flowering stems more or less terete, hairy all round; plants more or less creeping; leaves mostly thicker. 2. Plants forming dense tufts; leaves mostly narrow, elliptic, glabrous above, the nerves prominent beneath; upper calyx teeth nearly as long as broad l Th. serpyllum L. 2'. Plants forming rather loose tufts; leaves broader to nearly orbicular, mostly hairy above, the nerves scarcely prominent beneath; upper calyx teeth distinctly longer than broad. Th. humifusus Bernh. ex Rchb.