Page:The Zoologist, 1st series, vol 1 (1843).djvu/74

46 orders appeared first on the stage, and not the lower or worm-like fishes; so our author argues that the transition to reptiles was not by gradual progress, as the Lamarckian hypothesis would have it, for the higher or cartilaginous fishes were predominant during the enormous period represented by the five successive formations which preceded the commencement of the age of reptiles. The subject concludes thus: —

In proceeding to those discoveries for which we are peculiarly indebted to Mr. Miller, the Pterichthys, or winged fish, comes first in order, and is certainly the most interesting. In the system of Nature this strange creature would appear to be a cartilaginous fish, encased in the shell of an Echinus, the very tubercles of the shell bearing out the resemblance, and looking as though they had once served for the attachment of some armature analogous to that of the urchins. This idea seems strengthened by the opinion of Agassiz, who considers the wings of Pterichthys as weapons of defence only, like the occipital spines of the river bull-head; and capable of instantaneous erection on occasions of danger, but otherwise lying close by the creature's side. "The river bull-head, when attacked by an enemy, erects its spines at nearly right angles with the plates on its head, as if to render itself as difficult of being swallowed as possible." A first glance at the strong and seemingly sinewy arms of the Pterichthys would induce the belief that it moved with extreme velocity through the abyss of waters, but when stripped of this supposed activity by assigning another purpose to the arms, we have little more than a modified Echinus, and may suppose it invested with a similar ornamental panoply.

"Of all the organisms of the system, one of the most extraordinary, and in which Lamarck would have most delighted, is the Pterichthys, or winged fish, an ichthyolite which the writer had the pleasure of introducing to the acquaintance of geologists nearly three years ago, but which he first laid open to the light about seven years earlier. Had Lamarck been the discoverer, he would unquestionably have held that he had caught a fish almost in the act of wishing itself into a bird. There are wings