| The basic morphology consists of two nested, perforate cones connected by a series of septa. |
| Septal margins show conspicuous zones of irregular dissolution around interseptal spaces, but the zones do not occur where septa grew together. |
| It has dissepiments, but only a few large presepiments, so that most major septa are uninterrupted. |
| It may cause interstitial lung disease by diffusely involving the pleura, interlobular septa, and pulmonary bronchovascular bundles. |
| Adhesions are broad and very short septa between portal tracts and hepatic veins. |
| In the Middle and Late Silurian odd specializations, like lacunose septa and complex septal formations in the body chamber, develop. |
