Ultrastructural morphology of the nerve cells in the cerebral ganglion of the Acanthocephalan Moniliformis moniliformis.

The morphology of the cerebral ganglion of the Acanthocephalan Moniliformis moniliformis was studied in serial sections using electron microscopy. The organization of the cerebral ganglion was typical of other invertebrates with the cell bodies forming a rind, 1 cell thick, and their processes forming the central core of the neuropile. The ganglion was surrounded by a connective tissue capsule composed of collagen-like fibrils. Externally, the free surface of the cell bodies was covered by an electron-dense extracellular lamina. Seventy-six cells were identified in every ganglion examined and, on the basis of their cellular characteristics, they were divided into 5 distinct cell types, classified as type A, B, C, D and E cells. The characteristic morphological features of each cell type have been described, and the distribution of the different cell types in the cerebral ganglion was mapped.

The number and size of ovarian balls of Moniliformis (Acanthocephala) from laboratory rats.

By means of conventional light microscopical and counting procedures, estimations have been made of the average number and size of ovarian balls from unfertilized and fertilized female Moniliformis dubius. The observations were made on worms recovered from experimental primary infections lasting 1, 2, 3, 4, 5, 8, 11, 14, 17 and 20 weeks in male rats. The number of ovarian balls rises to about 6300 per worm, with the maximum being attained more rapidly in unfertilized than in fertilized females. On average more ovarian balls were present in unfertilized than in fertilized females, but a marked decline in number occurred in both groups of worms towards the end of the experimental period. Similarly, on the basis of the area within the elliptical profiles of fixed ovarian balls, it appeared that those from unfertilized females were generally larger on average than those from fertilized worms.