Diagrams showing the organisation of the tardigrade nervous system. Reconstructions of nerve tracts are based on anti-tubulin immunolabelling in Macrobiotus cf. harmsworthi. Anterior is up. (A) Ventral view. (B) Lateral view. Abbreviations: al, anterior leg nerve; as, anterolateral sensory field; br, brain; cl, cloacal nerves; cn, connective; dn, dorsolateral nerve tract; ga1–ga4, trunk ganglia 1 to 4; ic, inner connective; ip, interpedal commissure; le1–le4, legs 1 to 4; lg, leg ganglion; ln, lateral nerve tract; ne, neurites supplying the peribuccal lamellae; nr, nerve ring innervating the peribuccal lamellae; oc, outer connective; pg, peripheral ganglion; pl, posterior leg nerve; pn, peripheral nerve; ps, posterolateral sensory field.