Jörgensen

Jörgensen is a botanist and a former employee of the New York Museum of Natural History. Although retired, he still maintains an office at the museum. He is extremely tall, at least six feet four inches, but his posture is somewhat stooped with age. He is thin and bald with bushy white eyebrows and intense blue eyes.

Jörgensen was employed at the museum during the late 1980s and was involved with the early stages of the Whittlesey/Maxwell Expedition. He was a friend and colleague of John Whittlesey and Hugo Montague, but was excluded from the expedition when Edward Maxwell became involved. Jörgensen is still bitter about this, despite the fact that everyone that did go died.

Relic
Margo Green and Bill Smithback visited Jörgensen in his office to learn more about the expedition. He disliked Smithback and refused to speak to him, but told Margo what he knew: that Whittlesey intended to find the Kothoga tribe, still alive, on top of the tepui; that the Brazilian government refused him a permit to explore the southern area of the tepui, forcing the expedition to use the much more difficult northern approach; and that once in the field Whittlesey and Maxwell fought over whether to ascend the tepui despite the government's objections.

Jörgensen told Margo that Maxwell found some very unique plants at the base of the tepui, primitive ferms and orchids previously unknown to science. Maxwell's greatest discovery (in his own mind) were some large, wrinkled seed pods. These made it back to the museum in one of the crates and Margo's advisor Dr. Frock believed that the museum beast might have hatched from them. Jörgensen laughed at this suggestion and told Margo that Frock should stick to paleontology.

Jörgensen also told Margo about Hugo Montague, a Ph.D. candidate and protégé of Whittlesey. Montague did not go on the expedition but was in regular contact with its members until the plane crash that killed Maxwell's team. The expedition's crates were caught up in red tape for a further two years after the crash. When they finally arrived at the museum, only Montague was excited to receive them. He was given the job of curating the crates and did catalogue all of Whittlesey's artifacts, but then disappeared suddenly and mysteriously.

Jörgensen, who called Montague a "strange character" assumed he had gone off to Nepal or Thailand to find himself, though he acknowledged the rumors about the Museum Beast that circulated during that time. He related to Margo and Smithback one of the Kothoga legends Whittlesey had told him, about how the tribe made a deal with the devil Zilashkee, in which they performed horrible sacrifices in return for the god's protection. Zilashkee sent the tribe his son, Mbwun, whose name meant "he who walks on all fours".

Blue Labyrinth
Many years after the events of Relic, Margo Green returned to the museum to help Pendergast and Constance Greene investigate a mysterious elixir formulated by Pendergast's ancestor Hezekiah Pendergast. Margo visited Jörgensen, who still had an office in the museum years after his retirement, to ask about a plant called Thismia americana.

Jörgensen told Margo that the plant was extinct, but that the museum still had some specimens. He then showed her an internal memo from Morris Frisby, a director at the museum, informing the staff that Margo's access to the museum collections had been revoked. Jörgensen refused to help her, so she devised a plan to lure him out of his office and gain access to the code for the museum's herbarium vault.

Disguising her voice, Margo pretended to be a member of the botany department staff and told Frisby's secretary that Jörgensen was planning to give Margo access to the collections. Jörgensen was called down to Frisby's office to account for himself, and Margo slipped in and learned the code.