< Page:Popular Science Monthly Volume 11.djvu
This page has been validated.
189
GAR-PIKES, OLD AND YOUNG.

previously examined by naturalists (so far as known to the writer), but they also furnish the clew to the double tail, and suggest some important paleontological considerations.

While earnestly expressing his appreciation of the value of these little gars, the writer finds himself compelled to exemplify the proverbially ungrateful and dissatisfied nature of zoölogists by regretting that there were not more of them, and that some were not very much smaller, or even still within the egg.

In this connection one is reminded that now, as a rule, the smallest rather than the largest are desired by naturalists. The giants are curiosities, and interesting as showing the capacity for growth; but the mysteries of development, the relations of apparently diverse forms, and the order of geological succession, are best revealed by the apparently most insignificant.

A good illustration of this inverse ratio between size and value is contained in the following passage from Prof, and Mrs. Agassiz's "Journey in Brazil:"

"Mr. Agassiz has a corps of little boys, engaged in catching the tiniest fishes, so insignificant in size that the regular fishermen, who can never be made to understand that a fish which is not good to eat can serve any useful purpose, always throw them away. Nevertheless, these are among the most instructive specimens for the ichthyologist, because they often reveal the relations not only between parent and offspring, but wider relations between groups."

Of the two smallest gars, one is nearly colorless, while the other is marked very much as are the older ones. They are 18 millimetres (a little less than three-fourths of an inch) in length. The head is short and flattened, with slight indications of teeth on the edges of the jaws. With one of them the ventral fins have not appeared; with the other they are represented by minute white elevations. Each pectoral consists of a fleshy lobe, surrounded by a thin fringe or border.

Fig. 9.—Smallest Gar-Pike yet obtained (Eighteen Millimetres or about Three-fourth inch long, enlarged Five Diameters).
The actual length is indicated by the line above the figure. There are no scales. The head is short. The pectoral fin (P) consists of a fleshy lobe (L), with a thin fringe or border (F). The ventral fins have not appeared. A median fin extends along the hinder third of the body above and the hinder half below. It is interrupted hy the vent (V), and presents lour darker and more or less differentiated spots. The anterior pair are evidently the beginnings of the dorsal (D) and anal fins. The signification of the hinder dorsal spot is uncertain. But the hinder spot below (C) presents rays, and is the commencement of the infra-caudal lobe.

The hinder end of the body tapers to a point, as with Amphioxus, the extremity being slightly bent downward. At the junction of the middle with the hinder third of the body commences a delicate median fin, colorless, and without rays for the most part, and extend-

    This article is issued from Wikisource. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.