A tail draggin' Diplodocus and a pair of "amphibious" brontosaurs, published in the December 11, 1904 New York Tribune Illustrated Supplement. Via the LOC Flickr stream.
Here's a delightful excerpt from the accompanying story:
The appearance of a herd of these great monsters of past ages trooping down Broadway, uncontrolled, would cause an absolute cessation of business there. The street would be cleared with alacrity. The hallways of every building along the street would lie tilled instantaneously, and every elevator glutted with humanity fleeing for safety to the upper stories of the sky-scrapers. Those who preserved their mental equilibrium sufficiently to gaze calmly forth upon the procession of strange beasts as they passed in front of the buildings would be struck with several things. Perhaps they might think of Noah's problem with added respect...There's a lot more where that came from, too. I may not have gotten it totally correct - the scan was full to the brim with OCR errors. Check out a PDF of the page here.