Studies on the Life History and Development of Macracanthorhynchus ingens Meyer, 1933, with a Redescription of the Adult Worm

This worm was first described by von Linstow (1879) as Echinorhynchus ingens. Travassos (1917) placed it in the genus Prosthenorchis. Meyer (1933) removed it from Prosthenorchis and included it in the genus Macracanthorhynchus on the basis of the large size of the body and the nature of the outer shell of the egg. Meyer's description of the species, taken from von Linstow's original description, contains only the following meager data: Body 145 mm long, 3 mm wide, irregularly wrinkled. Proboscis with 6 rows of hooks (transverse rows), hooks 0.23 mm long. Eggs 0.098 mm long, 0.056 mm wide, dark-brown in color and ellipsoidal in shape and have a double shell the outer of which is characterized by a fine network of ridges. Recorded from Procyon lotor lotor L. Since this description is inadequate in many respects, the following more extended description is given: