The mystery of the stone heaps.

May 8. 

P. M. — To stone-heaps.

Mr. Wright of the factory village, with whom I talked yesterday, an old fisherman, remembers the lamprey eels well, which he used to see in the Assabet there, but thinks that there have been none in the river for a dozen years and that the stone-heaps are not made by them. 

I saw one apparently just formed yesterday. Could find none April 15th. This afternoon I overhaul two new ones in the river opposite Prescott Barrett's, and get up more than a peck of stones. The nests are quite large and very high, rising to within a foot of the surface where the water is some three feet deep.

I cannot detect any ova or young fishes or eels in the heap, but a great many insects, pashas with two tails, and, I think, some little leeches only. The larger stones are a little larger than a hen's egg, but the greater part of the heap is merely a coarse gravel. 

I see a great deal of the oat spawn, generally just flatted out, in that long pokelogan by the Assabet Bath-Place. It is over the coarse, weedy (pontederia and yellow lily stubble), and not the grassy bottom, commonly where there is more or less water all summer. 

The herb-of-St.-Barbara. 

Broke off a twig of Prichard's Canada plum in the evening, from which I judge that it may have opened to-day.

H. D. Thoreau, Journal, May 8, 1858

Mr. Wright , an old fisherman, thinks the stone-heaps are not made by lamprey . See May 4, 1858 ("I asked him if he knew what fish made the stone-heaps in the river. He said the lamprey eel.")

The herb-of-St.-Barbara.   See May 14, 1857 ("Herb-of-St.-Barbara, how long?")

I judge that Prichard's Canada plum may have opened to-day. See note to May 10, 1856 (“Mr. Prichard’s Canada plum will open as soon as it is fair weather.”)