Frogs are strange creatures.

April 18.

April 18, 2018

P. M. – To Hubbard's Grove. 

A dandelion open; will shed pollen to-morrow. 

The Rana sylvatica tadpoles have mostly wiggled away from the ova. 

Put some R. halecina spawn which has flatted out in a ditch on Hubbard’s land. 

I saw in those ditches many small pickerel, landlocked, which appeared to be transversely barred! They bury themselves in the mud at my approach.

Examined the pools and ditches in that neighborhood, i.e. of Skull-Cap Ditch, for frogs. All that I saw distinctly, except two R. fontinalis, were what I have considered young bullfrogs, middling-sized frogs with a greenish-brown back and a throat commonly white or whitish. 

I saw in a deep and cold pool some spawn placed just like that of the R. sylvatica and the R. halecina, – it was in the open field, – and the only frog I could distinguish near it was a middling sized one, or larger, with a yellow throat, not distinctly green, but brown or greenish-brown above, but green along each upper jaw. A small portion of bright golden ring about the eye was to be seen in front. 

In the spring near by, I see two unquestionable R. fontinalis, one much the largest and with brighter mottlings, probably on account of the season. The upper and forward part of their bodies distinct green, but their throats, white or whitish, not yellow. 

There were also two small and dark-colored frogs, yet with a little green tinge about the snouts, in the same spring.

I suspect that all these frogs may be the R. fontinalis, and none of them bullfrogs. Certainly those two unquestionable R. fontinalis had no yellow to throats, and probably they vary very much in the greenness of the back. Those two were not so much barred on the legs as mottled, and in one the mottlings had quite bright halos. They had the yellow segment in front part of eye, as also had the two smallest. Have the bullfrogs this? I doubt if I have seen a bullfrog yet.

I should say, with regard to that spawn, that I heard in the neighboring pool the stertorous tut tut tut like the R. halecina, and also one dump sound.

Frogs are strange creatures. One would describe them as peculiarly wary and timid, another as equally bold and imperturbable. 

All that is required in studying them is patience. You will sometimes walk a long way along a ditch and hear twenty or more leap in one after another before you, and see where they rippled the water, without getting sight of one of them. 

Sometimes, as this afternoon the two R. fontinalis, when you approach a pool or spring a frog hops in and buries itself at the bottom. You sit down on the brink and wait patiently for his reappearance. After a quarter of an hour or more he is sure to rise to the surface and put out his nose quietly without making a ripple, eying you steadily. At length he becomes as curious about you as you can be about him. He suddenly hops straight toward [you], pausing within a foot, and takes a near and leisurely view of you.

Perchance you may now scratch its nose with your finger and examine it to your heart's content, for it is become as imperturbable as it was shy before. You conquer them by superior patience and immovableness; not by quickness, but by slowness; not by heat, but by coldness. 

You see only a pair of heels disappearing in the weedy bottom, and, saving a few insects, the pool becomes as smooth as a mirror and apparently as uninhabited. At length, after half an hour, you detect a frog's snout and a pair of eyes above the green slime, turned toward you, -etc.

It is evident that the frog spawn is not accidentally placed, simply adhering to the stubble that may be nearest, but the frog chooses a convenient place to deposit it; for in the above-named pool there was no stout stubble rising above the surface except at one side, and there the spawn was placed.

It is remarkable how much the musquash cuts up the weeds at the bottom of pools and ditches, – burreed, sweet flags, pontederia, yellow lily, fine, grass like rushes, and now you see it floating on the surface, sometimes apparently where it has merely burrowed along the bottom.

I see where a ditch was cut a few years ago in a winding course, and now a young hedge of alders is springing up from the bottom on one side, winding with the ditch. The seed has evidently been caught in it, as in a trap.

H. D. Thoreau, Journal, April 18, 1858

A dandelion open; will shed pollen to-morrow. See April 18, 1860 ("Melvin has seen a dandelion in bloom. "). See also April 29, 1857 ("I commonly meet with the earliest dandelion set in the midst of some liquid green patch. It seems a sudden and decided progress in the season.")

I suspect that all these frogs may be the R. fontinalis, and none of them bullfrogs. See  April 5, 1858 ("What I call the young bullfrog, about two and a half inches long, — though it has no yellow on throat. It has a bright-golden ring outside of the iris as far as I can see round it. Is this the case with the bullfrog? May it not be a young Rana fontinalis?"); see also Peabody Museum,  Green Frog - Rana clamitans ("often green, however, dorsal coloration can also be brown, black or even grayish. The upper lip is usually bright green, but not always. ... Often confused with the American Bullfrog, which lacks the complete dorsolateral ridge and has a yellow-green belly.")

You conquer them by superior patience and immovableness; not by quickness, but by slowness. See April 15, 1858 ("The naturalist accomplishes a great deal by patience, more perhaps than by activity. He must take his position, and then wait and watch. It is equally true of quadrupeds and reptiles. Sit still in the midst of their haunts. ")