Xylotheque

 ( Wood ) 

In older xylotheques, the wooden volumes were typically made out of the same wood as the specimens inside and sometimes decorated with tree bark and associated lichens and mosses. Each volume housed seeds, flowers, twigs, and leaves from the corresponding tree or bush, along with a written description hidden in a small compartment set into the inner spine. An alternative form of xylotheque found in Japan and elsewhere featured paintings of the plant parts rather than actual field specimens.

Even a modest collection of wood samples has value, as each of its samples has a particular history. Xylotheques provide comparison samples for xylotomy, art historical studies, and scientific studies of the physical and mechanics properties of wood, such as durability and preservation. Xylotheques are also useful for anyone who needs to make a morphological-visual analysis of wood.

The xylotheque with the largest number of samples is the Samuel James Record Collection in the United States, which holds 98,000 samples. Formerly housed at the Forestry School of Yale University in New Haven, Connecticut, it was transferred to the U.S. Forest Service's Forest Products Laboratory in 1969. The second largest xylotheque belongs to the Royal Museum of Central Africa in Tervuren, Belgium, with 57,000 samples. The Thünen Institute of Wood Research in Hamburg has more than 37,000 samples.

Below is a list of the Index xylariorum codes, locations, and institutional names included by Stern in his 1988 Index xylariorum. This list is provided for historic context.