THE PEABODY MUSEVM. 405C 



divided into two orders, according as they have their teeth set in grooves or 

 in distinct sockets. Of some of these the skeletons are almost complete as 

 to individual birds ; and Prof. Marsh is at present engaged upon a large and 

 elaborate monograph on this subject, describing and illustrating the new 

 forms by copious engraved drawings; one of the rooms on the second fioor 

 is at present occupied by the skilled assistants and draughtsmen engaged 

 upon this important memoir. Another of the alliances between birds and 

 reptiles, of which the birds with teeth supply such remarkable examples, is 

 suggested by the jjterodactyls, or flying lizards of the same cretaceous beds 

 in Kansas. Prof. Marsh was the first to find any ^Pterodactyls in America; 

 these are of enormous size, the spread of their wings being from ten to 

 twenty-five feet. The singular feature about these reptiles from American 

 rocks is that they had no teeth, and hence in this respect they resemble the 

 modern birds. The remains of other reptiles have been discovered in the 

 cretaceous beds of the West, and the specimens here brought together include 

 the bones of several thousand individuals. From these abundant remains 

 Prof Marsh has been able to determine many doubtful points, such for in- 

 atance as that the mosasaur^ had hind limbs or paddles, and that they were 

 covered, at least in part, -with hard, bony scales. The mosasaurs were sea- 

 serpents, from ten to sixty feet in length. Bosides these, there are here also 

 the remains of gigantic crocodiles, lizards, turtles and snakes, any one group 

 of which would make the reputation of an ordinary museum. Of the enor- 

 mous reptiles of geology, none yet known surpassed in size one which Prof 

 Marsh has recently described. Its remains were found in the cretaceous 

 beds of Colorado; it is named Titanosaurus montanus ; it Avas herbivorous, 

 and attained a length of fifty to sixty feet. Believers in a vegetarian diet 

 should take note of these facts, as that saurian was the largest land animal 

 known to have existed on this planet. The reptile will also supply a bone 

 to pick, that will puzzle people who have assumed that animal life in this 

 hemisphere has been in general represented by smaller forms than the cor- 

 responding ones of other continents. If the question of size should ever be 

 raised as to the mammals of the West, the Peabody Museum can show the 

 remains of more than one hundred distinct individuals of the dinoceras kind 

 — a new order of mammals from the Eocene of the Eocky Mountains, nearly 

 equal to the elephant in point of size, and armed with four to six horns, as 

 well as formidable tusks ; or point to the brontotherium of the miocene rocks 

 — a creature as large as the dinoceras, and also armed with horns. The 

 oldestjknown member of the rhinoceros family, perhaps its progenitor, has 

 been discovered b}^ Prof. Marsh in the upper eocene of Utah. From the 

 lower beds of the same formation in Wyoming Territory came the tillodonts, 

 perhaps the strangest of all Eocene mammals, as they seeia to combine char- 

 acteristics of the carnivora, rodents, and ungulates. There, also, the same 

 discoverer first found the JSTorth American monkeys, which are allied on the 

 one side to the lemurs of the Eastern Hemisphere, and on the other to the 

 monkeys of South America. 



