|Description=Anatomy - features of the Muscular system |Source=[[Encyclopædia Britannica Eleventh Edition]], Vol. 1, Page 940 |Date=1911 |Author=Encyclopædia
Description1911 Britannica-Arachnida-Lankester2.png English: From Ray Lankester, “Limulus an Arachnid.” The alimentary canal and gastric glands of a scorpio
Description1911 Britannica - Transverse sections of Amphioxus.png English: Transverse sections of Amphioxus. (From Lankester.) A. Section through region