Robert Hooke read his Letter L-117 of 1682-03-20 and Leeuwenhoek's reply, Letter L-119 of 1682-04-04 about muscles of crabs, lobsters, and shrimp
At the Wednesday 5 April 1682 (O.S.) meeting of the Royal Society, Hooke read his letter to Leeuwenhoek of 1682-03-10 (O.S.) and Leeuwenhoek's reply, Letter 36 of 1682-04-04. Hooke published both in his Philosophical Collections, no. 7, pp. 188-89.
Birch, History, vol. IV, p. 140, 5 April 1682 (O.S.) in London:
Mr. HOOKE read a letter, which he had sent to Mr. LEEWENHOECK concerning the discoveries, which he had made and shewn the Society four or five years before of the figure of the fibrills of the muscles of crabs, lobsters and shrimps, &c. viz. that they in appearance through a microscope resembled a necklace of seed pearl; and that every one of those fibrills, which was not much above a hundredth part of the bigness of an hair, seemed to be distinct strings of pearls or bullets; and that the whole bulk of the fleshy part of those muscles was made up of an infinite number of those fibrills lying parallel by one another; but that he had not hitherto been able to see that figure in the fibrills of the muscles of the flesh.
He also read a letter from Mr. LEEWENHOECK in answer to the same, dated at Delft 4 April, 1682, N. S. giving an account, that he had at the desire of Mr. HOOKE viewed the muscles of crabs and shrimps and had found the same appearance; but that he had difscovered them to be of the fame nature with the rimples in the fibrills of flesh-muscles; and to be composed of other less fibrills, as are those of flesh.