On the origin and evolution of major morphological characters.

No single morphological character appears to be diagnostic of the order Asparagales.

Several morphological characters have been analysed and found not to conflict with the molecular data.

Some studies have combined morphological and molecular characters in their analyses.

There are however no known morphological characters that would clearly distinguish it from the others.

Dugesia species have not enough morphological characters to find out which are the relationships between them.

The two species differ in a number of morphological characters in addition to size.

Clarke lists the following morphological characters that distinguish the two species.

It is to me delightful to see what appears a mere morphological character found to be of use.

However, closer examination of less obvious morphological characters seemed to show that they were not even closely related.