Dry rot The term "dry rot", or "true dry rot", refers to the decay of timbers from only certain species of fungi that are thought to provide their own source of moisture and nutrients to cause decay in otherwise relatively dry timber. However, there has been no published experimental evidence to support the phenomenon. In modern texts, the term 'dry rot' is used in reference to damage inflicted by either: "Serpula lacrymans" (formerly "Merulius lacrymans") predominantly in the United Kingdom and northern Europe; and/or "Meruliporia incrassata" (which has a number of synonyms, including "Poria incrassata" and "Serpula incrassata") in North America. Both
Serpula tidal fashion. In the central circulatory system, the blood moves anteriorly from the tip of the abdomen to the front of the thorax through a sinus enveloping the alimentary canal, and posteriorly through a ventral blood vessel. The ventral vessel and the sinus communicate with each other by segmentally arranged ring vessels, and by a dorsal vessel, a transverse vessel, and a pair of circumesophageal vessels situated at the anterior end of the thorax. The dorsal vessel in some of the larger serpulids, like "Serpula", possesses a valve and a muscular sphincter, probably to prevent backflow of blood from the