The only animal inhabitants of these Devonian woods, so far as known, were a few species of insects, discovered by Hartt in New Brunswick, and described by Dr. Scudder. Since, however, we now know that scorpions as well as insects existed in the Silurian, it is probable that these also occurred in the Erian, though their remains have not yet been discovered. All the known insects of the Erian woods are allies of the shad-flies and grasshoppers (_Neuroptera_ and _Orthoptera_), or intermediate between the two. It is probable that the larvæ of most of them lived in water and fed upon the abundant vegetable matter there, or on the numerous minute crustaceans and worms. There were no land vertebrates, so far as known, but there were fishes (_Dipterus_, etc.), allied to the modern Barramunda or _Ceratodus_ of Australia, and with teeth suited for grinding vegetable food. It is also possible that some of the smaller plate-covered fishes (Placoganoids, like _Pterichthys_) might have fed on vegetable matter, and, in any case, if they fed on lower animals, the latter must have subsisted on plants. I mention these facts to show that the superabundant vegetation of this age, whether aquatic or terrestrial, was not wholly useless to animals. It is quite likely, also, that we have yet much to learn of the animal life of the Erian swamps and woods. NOTES TO CHAPTER III. I.--Classification of Sporangites. It is, of course, very unsatisfactory to give names to mere fragments of plants, yet it seems very desirable to have some means of arranging them. With respect to the organisms described above, which were originally called by me _Sporangites_, under the supposition that they were Sporangia rather than spores, this name has so far been vindicated by the discovery of the spore-cases belonging to them, so that I think it may still be retained as a provisional name; but I would designate the whole as _Protosalviniæ_, meaning thereby plants with rhizocarpean affinities, though possibly when better understood belonging to different genera. We may under these names speak of their detached discs as macrospores and of their cellular envelopes as sporocarps. The following may be recognized as distinct forms: