I have made the drawings below in 1977. I found these tests in sediment of peat bogs in het Hol, the Netherlands.
This test contained a remarkable small cell which didn’t fill the test as usual. Both are tests of Lacogromia cassipara.
Two different tests, one small, (Allogromia nigricans?) the other broader and also much larger. The latter contained a living cell which had a large nucleus, in which I could not detect any structure. The cytoplasm was black-brown and contained small reddish peanut-shaped granules, the membrane of the test was grey.
Two large empty tests, with distinct collars, which is typical for Lacogromia cassipara morphotype B.
I found three shells of Lacogromia cassipara with a living cell inside. One individual contained c. 8 nuclei (left), the other two had only one nucleus. All nuclei were 40-42 µm in diameter.
Four empty shells in the sediment of a peat bog. Note the difference in shape.
Two living cells, one 268 µm long and the other 120 µm. Both cells had a distinct peduncle. The large cell contained c. 30 nuclei, each 12 µm in diameter, and the other cell 3 nuclei, size unknown.
Lacogromia cassipara, with one nucleus and a distinct peduncle or Pseudopodienstiel, photographed 1983.