Van Heurck -- Synopsis des Diatomées de Belgique -- Index
| Plagiogramma | gregorianum Grev. | Page 145 | Plate 36 | Figure 2 | |
| Plagiogramma | interruptum var. ? adriatica Grunow | Page -- | Plate 36 | Figure 1 | |
| Plagiogramma | ornatum var. ? undulatum Grunow = Plagiogramma undulatum Grunow | Page -- | Plate 36 | Figure 3 | |
| Plagiogramma | undulatum Grunow | Page -- | Plate 36 | Figure 3 | |
| Plagiogramma | vanheurckii Grunow | Page 145 | Plate 36 | Figure 4 |