That baptismal rite produced a description which has stuck to this day and I still use his description when I show this tunicate to new, unsuspecting visitors. However, I also took his remark as a challenge to show him how fascinating and idiosyncratic Styela plicata is. The tunic is a real oddity in the animal world, for it consists largely of cellulose compounds. It is tough, gristly, warty and ridged. The vessels have a membrane dividing them which allows fluid to flow up one side and down the other.
Tunicates have an incurrent siphon and an excurrent siphon.
Water containing minute food particles is admitted through the incurrent siphon into the pharyngeal basket. This basket is an elegant structure designed rather like a net or lacy lattice. There the food is digested and the waste is passed on into the anus which opens into the excurrent siphon and is there ejected. It is difficult to generalize about tunicates, because they show such an amazing diversity. They belong to the phylum Urochordata .