Ixx THE ANIMAL KINGDOM. 



dition placed him next to Milne-Edwards at the head of living authors in this depart- 

 ment, and his essay on their geographical distribution is the starting-point for all such 

 inquiries. The North American species have been described by Say, W. Stimpson, 

 J. W. Randall, L. R. Gibbes, S. I. Smith, Hagen, W. N. Locldngton, E. A. Birge, 

 C. L. Herrick, W. Faxon, Packard, O. Harger, and J. S. Kingsley, and the fossil forms 

 by Green, Hall, Billings, Stimpson, Packard, C. E. Beecher, Clarke, C. D. Walcott, 

 and others. 



The intestinal and higher worms have been worked up by D. Weinland, Girard, 

 Leidy, Wyman, Verrill, Stimpson, Minot, Webster, Benedict, Sager, Whitman, 

 and Wright ; and of the aberrant classes some of the Polyzoa have been carefully 

 studied by A. Hyatt, and the Brachiopoda by E. S. Morse and W. H. Dall. 



The molluscs of North America have been elaborated by Say, Gould, Lesueur, 

 Rafinesque, Haldeman, I. Lea, T. A. Conrad, Anthony, C. B. Adams, Stimpson, the 

 two Binneys, J. W. Mighels, J. P. Couthouy, Gabb, A. Agassiz, T. Bland, T. Prime, 

 Morse, J. Lewis, Dall, Tryon, Verrill, R. E. C. Stearns, Sanderson Smith, and others. 

 The fossil Mollusca of entire formations have been described by Hall, Billings (of 

 Canada), F. B. Meek, C. A. White, F. S. Holmes, O. St. John, C. F. Hartt, R. Rath- 

 bun, O. A. Derby, Whitfield, N. S. Shaler, Whiteaves (of Canada), and other palseou- 

 tologists; and the quaternary species studied by Holmes, Dawson, Stimpson, Packard, 

 Yerrill, Matthews, and others. Tbeir anatomy has been studied by Leidy, Wyman, 

 Morse, Dall, W. K. Brooks, and H. L. Osborn ; while B. Sharp has studied their 

 visual organs. 



The coelenterates and echinoderms have been carefully elaborated by Louis and A. 

 Agassiz, and by Say, Stimpson, E. Desor, Ayres, Macrady, H. J. Clark, T. Lyman, 

 Pourtales, Verrill, W. K. Brooks, S. F. Clarke, E. B. Wilson, J. S. Kingsley, J. W. 

 Fewkes, H. W. Conn, and H. G. Beyer ; while Dana's elaborate report on the Zoo- 

 phytes of the L^nited States Exploring Expedition took the highest rank among syste- 

 matic works. Numerous fossil forms have been brought to light by Hall, Billings, 

 Meek, Shumard, Springer, White, Wachsmutli, Wiiitfield, W. H. Niles, O. A. Derby, 

 and other palaeontologists, and the distribution of the recent forms on both sides of 

 the continent has been studied by Verrill and A. Agassiz. 



The sponges have been chiefly studied by Clark, Hyatt, Potts, and Mills ; and the 

 Protozoa by Leidy, J. W. Bailey, H. J. Clark, A. C. Stokes, J. A. Ryder, and D. S. 

 Kellicott. 



We may congratulate ourselves on the high position of our paleontologists in the 

 scientific world. The labors of James Hall, Meek, Billings, Dawson (of Montreal; 

 we include Canadian students), and others, have revealed whole platforms of life in 

 the palaeozoic rocks ; while the researches of Leidy, Cope, Marsh, and W. B. Scott and 

 H. F. Osborne, in the tertiary, cretaceous, and Permian beds of New Jersey and the 

 west, and of Deane, Hitchcock, Leidy, Wyman, Newberry, Emmons, and Cope, in 

 triassic and carboniferous strata, have been j)roducti\e of valuable results. 



The discovery of the fossil bird-like reptiles of New Jersey, by Leidy and Cope ; 

 of birds with teeth, and pterodactyls without teeth ; of lemur-like monkeys, by 

 Marsh ; of camels, by Cope ; and the discovery by Leidy, Marsh, and Cope, of con- 

 necting links between living ruminants and hog-like forms, and between elephants 

 and tapirs ; together with the genealogy of the horse, and the increase in the size of the 

 brain of living forms over their tertiary ancestors, as elaborated by Marsh, all present 

 a mass of new facts bearing on the evolution of life on the American continent, and 



