Yugoslavia
The olm or proteus (Proteus anguinus) is an aquatic salamander in the family Proteidae, the only exclusively cave-dwelling chordate species found in Europe. (Postojna Cave, Slovenia)
| Country: | Yugoslavia |
| Type: | Postage stamps |
| Series: | Fauna (1954) |
| Nominal: | 70 din. |
| Year: | 1954 |
| Material: | coated with silk fiber |
| Size: | 26.5 x 36.5 mm |
| Perforation: | comb 11¾ |
| Mintage: | 100,000 |
Fauna (1954)
 European Ground Squirrel 0.05$ |  Eurasian Lynx 0.1$ |  Red Deer 0.18$ |  Brown Bear |
 Chamois 0.12$ |  Great White Pelican 0.64$ |  Bearded Vulture |  Ground Beetle 0.51$ |
 Cricket 0.77$ |  Dalmatian Wall Lizard |  Olm |  Brown Trout 34$ |