| PASSENGERPIGEON | North American bird which once numbered in the billions but became extinct in the early 1900s (9.6) |
| QUAGGA | Zebra subspecies that became extinct in the 1880s |
| GATES | Bill in the billions |
| EAGLE | Bird which once landed on the moon? (5) |
| DODO | Extinct flightless bird which once inhabited Mauritius (4) |
| BALDEAGLE | This bird may have numbered in the hundreds of thousands when it was declared the American national bird in 1782, but its numbers steadily declined over the next two centuries, owing primarily to huma |
| CIA | Org. in David E. Hoffman's book "The Billion Dollar Spy" |
| VERSE | It's numbered in the Bible |
| BUSTARD | The great ____, a chalk downland bird in southern England, became extinct in 1832, and was reintroduced on Salisbury Plain in 2003 |
| HEATHHEN | A bird of the grouse family in North America that became extinct in 1932 (5,3) |
| MANMOUNTAINDEAN | Frank Leavitt, wrestler of the early 1900s, better known by this name |
| ROALDAMUNDSEN | Norwegian explorer who led the first expedition to the South Pole in the early 1900s: 2 wds. |
| WRIGLEY | In the early 1900s, which chewing gum manufacturer was the US's biggest advertiser? (7) |
| RAGTIME | Kind of jazz piano music invented in the U.S. in the early 1900s (7) |
| PEREDAVIDSDEER | Large animal, a native of China but now extinct in the wild, also called the elaphure (4,6,4) |
| PATHE | Which French company led the filmmaking world in the early 1900s? (5) |
| PIPECLEANERS | Wire brushes used in crafting invented by John Harry Stedman and Charles Angel in Rochester, New York in the early 1900s (4,8) |
| PAPER | Now known as a tissue, the ... handkerchief came into use in the early 1900s |
| GOSHAWK | Bird of prey once almost extinct in the UK (7) |
| GOLDENFROG | The National Zoo is one of several facilities worldwide reviving the population of this striking-looking Panamanian jumper, now thought to be extinct in the wild |