The works of Francis Maitland Balfour, Volume 3 (of 4)

by Francis M. Balfour

Natantia ex. Pyrosoma.

C. Conserta

Salpidæ.

Doliolidæ.

II. Perennichordata.

Ex. Appendicularia.

[6] It is more probable that this part of the alimentary tract is equivalent to the postanal gut of many Vertebrata, which is at first a complete tube, but disappears later by the simple absorption of the walls.

[7] It is probable that these papillæ are very primitive organs of the Chordata. Structures, which are probably of the same nature, are formed behind the mouth in the larvæ of Amphibia, and in front of the mouth in the larvæ of Ganoids (Acipenser, Lepidosteus), and are used by these larvæ for attaching themselves.

[8] For a fuller account of the organs of sense vide the chapters on the eye and ear.

[9] The account of the multiplication of the branchial clefts is taken from Krohn’s paper on Phallusia mammillata (No. [24]), but there is every reason to think that it holds true in the main for simple Ascidians.