eral were certain to be caught. They fed ravenously at this time, and even when confined in very cramped quarters, would devour any flies that came within reach. On the other hand, they were the main food-supply of certain fishes, all the snakes, the turtles, and a few species of birds.

I found that all our snakes at this time (April and May) were more abundant in the meadows than elsewhere, and have no doubt were drawn thither for the purpose of feeding on these little batrachians. Even that lover of high, dry and dusty fields, the hog-nosed snake (Heterodon platyrhinus) was found to be stationed at intervals along the ditch banks, on the lookout for 'peepers;" the dissection of one of these snakes proved that it had fed upon these small frogs.

About the 20th of May there was a very noticeable diminution of their numbers, and by the 10th of June not a specimen was to be found.

The fact is, that their vigor culminates with the maturity of the ova and spermatozoa, and having spawned, they have no vital force remaining, and in the course of a few days after ovipositing, they die. Weeks then elapse when no representatives of this batrachian are to be found; indeed none exist, except the thousands of tadpoles. Late in August these tadpoles had become fully developed "peepers." Even then they were very rare during that summer (I suppose this is always the case), but in September many were found in damp places, never in the water, but always near a running brook, or a spring. By the middle of September a marked increase in their numbers was noticed; but their haunts were different. I found very few in the meadows, but many in damp places, as spring holes, in the adjacent woodland, and particularly along a brook where the water flows rapidly over a rocky bed.

It was here that I closed my field studies of these batrachians. Early in October I found a number of these "peepers" in a little ravine through which the above-mentioned brook passes. I noticed at this time, that these little creatures had a decided aversion to the water. Necessary as it was for them to keep their skins moist, they had no desire to become thoroughly wetted, and when by chance they made an unlucky jump and settled in the water, they straightway crawled out and took up a high and dry position on some projecting stone. If in the sun-light so

much the better. A bath seemed to chill them, and whenever I drove one into the water, I found that for several minutes after it emerged I could pick it up without difficulty; but in time it would regain its ordinary activity, and then quick indeed must be one's movements who would catch them with the hand alone.

It was at this time, too, that I gave close attention to the subject of their color and its changeableness.

While there are certain peculiarities of color that are persistent and characteristic of the species, these become of little prominence at times, so very great is the difference in the entire coloration of the animal. Furthermore, they change their hues with great rapidity, and during the course of a few moments will pass from an ashy paleness or clay color, to an intense black, with the light dorsal stripe scarcely visible, or else either a glowing red or brilliant metallic green. So very beautiful are these changes, and so different will any half dozen prove to be, that it is difficult to realize that the many before you are one and the same species. Of a series of six which I have long kept in confinement (October 20th to January 29th) in a bottle, one specimen was taken from a ledge of pale yellow clay. The "peeper" was of the same color, the post-orbital dark spot and light dorsal line being scarcely discernible. The uniform yellow tint, however, was relieved by minute round points of brilliant bronze. This individual, unlike its companions, did not alter in color for several weeks. The others were very changeable, and particularly so when exposed to direct sun-light. While I noted several instances to the contrary, my impression is that usually the colors pale in direct sun-light, and deepen when the animals are in deep shade. This certainly is true of those I have in confinement,

and

agrees with my experience in searching for them during the past autumn. One fact with reference to the subject of their color is not in accordance, perhaps, with the above, but should not go unrecorded. The six individuals which I have in a bottle will, at times, present very different tints, although all are subjected to like surroundings. Of the six, two or three would be very dark, the others pale yellow. With some the dark triangular spot between the eyes would be very distinct, in the case of the others it could not be detected, even in outline. It must be remembered, however, that these individuals were kept in most

unnatural conditions, and had, at the time of this writing, been without food for one hundred days, and at the same time remained as active as squirrels.

Sensitive as these "peepers" are to changes of temperature, it is by no means the first frost that drives them into their winter quarters. In the autumn of the past year (1881) I found them last as late as Nov. 12th, but even later (Dec. 27th) my son found one in the meadows which was as lively as a cricket. The frogs generally were singing this day. For more than two weeks prior to Nov. 12th there had been several white frosts, and the true frogs (Rana) had all disappeared except such few as lingered in the warm waters of the larger springs. Not so, however, with the "peepers;" the cozy, sheltered nooks in the ravine I have mentioned, afforded them comfortable quarters still, and after a severe rainstorm which lasted for three days, I found numerous specimens near the brook, always in moist places but not where it would be called wet. In many instances they were found adhering to the under sides of projecting stones, roots of trees, and even to large oak leaves. I find it stated by De Kay in Natural History of New York, that they cannot retain their hold upon the under sides of projecting objects; that the discs on their toes are not sufficiently large. This is an error; indeed, the specimens I have in a bottle, can retain their hold when the bottle is turned over.

My impression is, that they do not require or partake of any food during their brief experience as matured "peepers" in autumn (i. e., from completion of the growth of their limbs in September to the commencement of their hibernation). My reason for this is based upon the fact that the specimens in a bottle, to which I have referred, were placed in confinement on the 20th of October, 1881, and the date of writing, Jan. 29, 1882, a period of one hundred days has just elapsed. During this time these "peepers" have had no food, have been quite as active as their limited quarters would permit, and yet have not lost weight to any important extent. One which I weighed on the day fol lowing its capture weighed forty-four grains, and seventy-five days later had lost but one grain in weight.

It is very different in the spring; then they are voracious feeders, and capture millions of minute insects. At this time their stomachs are always full; and while the size of the animal is not

larger than in autumn, the weight is nearly twice as great. Their physiological activity culminates with the maturing of the ova and the labor of depositing it; this effected, they are worn out and in a very short time, die.

:0:

THE EVOLUTION OF FORMS FROM THE CLINTON TO THE NIAGARA GROUP.

BY EUGENE N. S. RINGUEBERG.

WHILE collecting Niagara and Clinton fossils in the village of

Gasport during the fall of 1881, I was struck by the peculiarity of texture and character of the fossils contained in the upper band of limestone; which is there found superimposed upon the series forming the upper portion of the Clinton group proper, and I at once recognized a similarity between its fauna and structure, to an analogous layer which I had previously noticed in the western portion of the town of Lockport, but had failed to find at several other points of outcrop.

At the place where it was first noticed, however, its character, both in regard to the fossils contained, which there are generally rare and fragmentary, and the general appearance of the rock, is not so pronounced in distinction from the underlying strata as at Gasport.

This layer is not continuous, but apparently occurs in confined areas. Thus it is found at Gasport and again in the western portion of the town of Lockport. But in the city, about two miles east from the latter point, and on the same line of outcrop, whose general direction is from east to west, it is entirely wanting, as I have ascertained by a careful examination of both natural and artificial exposures at the line of juncture between the Niagara shale and Clinton limestone.

It is extremely variable in thickness, but I should judge its greatest development to be in the neighborhood of two feet. This is merely to be taken as an estimate, as I have not been able thus far to take the proper means of obtaining accurate

measurements.

The upper surface is extremely irregular and undulating; having the appearance of being drifted together. This is also corroborated by the position of many of the fossils, which seem to have been swept together by eddies, which at the same time were

charged with sedimentary matter by which they were entombed as we now find them.

Thus immense numbers of the cephalic and caudal shields of Illanus barriensis will be found in the space of perhaps ten or fifteen inches, and outside of this accumulation there will not be any except a stray one or so.

In one vertical section of the stone in my collection, two inches in diameter, the fracture shows thirteen shields of this trilobite crowded one above the other. It also does not seem to have any very regular lines of stratification. At Gasport the limestone has a light bluish tint, and breaks, when comparatively free from fossils, with a clean flinty fracture, and is very hard, fine grained and compact. The majority of the shells have the interior filled with crystallized calcite, and some of the larger cephalopods are lined with crystals of the same. From all information obtainable, it seems that this layer has always been associated with the Clinton group. Its fossils, however, prove that it is more closely allied to the Niagara.

The most common forms are Atrypa nodostriata and Meristina nitida, both of which are Niagara forms. After these we may cite Spirifera radiata, Lichenalia concentrica and Illanus barriensis; which are common to both. The first of these reaches its perfection in the Clinton, and is found in a minor degree in the subsequent shales of the Niagara, while the two last are but sparingly found in the Clinton, and are found in the greatest numbers at the opening of the Niagara series.

But the most striking feature of this limestone-for which I propose the name of the Niagara Transition Group-is the abundance and perfection of the Cephalopoda, which in all other strata of the Niagara period in Western New York are quite rare, with the exception of Orthoceras annulatum, which is found in moderate numbers in the Niagara shale and also is the most common of the Clinton forms. In this respect as in the identity of a number of species, we find a strong analogy to the limestones representing the Niagara group in the Western States. In it we find Cytoceras hercules, C. brevicorne, Trochoceras costatum, Trochonema pauper, Palæocardia cordiformis, etc., which will be recognized as western species.

The majority of the species, as will be seen by the following