A crop-like dilatation of the gut and a recurved intestine, embedded in the compact yellowish-brown liver, the ducts of which open into it, form the rest of the digestive tract and occupy a large bulk of the visceral hump. The buccal region presents a pair of shelly jaws placed laterally upon the lips, and a wide range of variation in the form of the denticles of the lingual ribbon or radula.
C, A young redia, the digestive tract shaded.
Formerly it was said that the head consisted of four the whole digestive tract may be ectodermal.
The digestive tract of Patella offers some interesting features.
But the larvae of the Ecaudata are mainly herbivorous and the digestive tract is accordingly extremely elongate and coiled up like the spring of a watch.