I found this story on Futility Closet here. The rest of the information has been supplemented by the Hoo-Hoo website (yes, it is still in existence) and, I'm sorry to say, Wikipedia. Here is a modern context:
"Hoo-Hoo was founded in 1892 in Gurdon, Arkansas, USA by five business travelers returning from a meeting of the Arkansas Yellow Pine Manufacturer's Association who had to wait several hours for their connecting train . . . The founders wanted the organization to be unconventional and unregimented. Its one aim would be 'to foster the health, happiness, and long life of its members'.
"In a spirit of fun, names for some of the officers were inspired by Lewis Carroll's The Hunting of the Snark. The chief executive officer of Hoo-Hoo is the Snark of the Universe (formerly the Grand Snark of the Universe). The Board of Directors includes the Chairman, Vice-President, Secretary-Treasurer, the Seer of the House of Ancients, and the Supreme Nines. The Supreme Nines include the Supreme Hoo-Hoo, Senior Hoo-Hoo, Junior Hoo-Hoo, Scrivenoter, Bojum, Jabberwock, Custocatian, Arcanoper and Gurdon. The Hoo-Hoo emblem is a black cat with its tail curled into the shape of a figure nine."
Basically, they are interested in the welfare of forests and the foresting industry. They go around doing good works and planting as many trees as possible. This organization has become so popular that not only are there monuments celebrating their charitable endeavors, but branches have spread world-wide.
In Miscellaneous Notes and Queries in January, 1897, the following story appeared, summarizing the Order in a really twisty and unhelpful way:
"Concatenated Order of Hoo Hoo. This is the name of a Western organization. It was organized by the ‘supreme nine.’ The Snark of the Universe is William Eddy Barns, of St. Louis, Mo. The other officers are designated Senior Hoo Hoo, Junior Hoo Hoo, Bojum, Scrivenoter, Bundersnatch, Custocatian, Arcanoper, Gurdon. There are 24 Vicegerent Snarks for as many States and Territories. This Order was founded in 1891 by nine traveling lumbermen, detained at Kansas City on account of a railroad wreck, and has extended over the Union.
"Its declared object is the promotion of the ‘health, happiness, and long life of its members.’ The membership is limited to 9,999. The symbol of the Order is a black cat with its back and tail up, chosen because of its traditional nine lives. Brethren are known as kittens. Hoo Hoo day is the ninth day of the ninth month of the year. The annual meeting begins the ninth minute after nine o’clock p.m. on that day. The initiation fee is $9.99, and the annual dues are 99 cents. There is a ritual, and aid is extended to distressed members and their families."
This second explanation provides almost no context. I can't imagine how confused the people reading this in 1897 must have been. Maybe that was the point. That said, those founding members sound like they had a grand old time. I most definitely would have been friends with those guys.