ClipArt ETC
"Amphioxus lanceolatus. A, transverse section of the pharyngeal region. a, dorsal aorta; b, atrium; c, notochord; co, coelom; e, endostyle; g, gonad; kb, branchial lamellae; kd, pharynx; l, liver; my, myomere; n, nephridium; r, neuron or dorsal nerve tube; sn, spinal nerves; sp, gill-slits. B, transverse section of the intestinal region; atr, atrium; coel, coelom; d. ao, dorsal aorta; int, intestine; myom, myomere; nch, notochord; neu, neuron; s. int. v, subintestinal vein." -Parker, 1900

Lancelet Section

"Amphioxus lanceolatus. A, transverse section of the pharyngeal region. a, dorsal aorta; b, atrium;…