466 RICHARD SWANN LUlJ. ON 



The last classification proposed hy Edward Hitchcock is that given in the Ichuology, 

 in IS-JS, and this remained unchanged until 1889 when his son, Prof. C. H. Hitchcock 

 ('89b), Wrought forth a new one in which dinosaurs were first recognized as the possible 

 makers of many of the tracks. This classification was republished in Professor Emerson's 

 Geology of Old Hampshire county, Massachusetts ('98. p. 4(»()-403) and owino- to error 

 was the same as that of 1889 though it was supposed to have been revised. In a 

 letter to the present author, dated April .3d. 1903, Professor Hitchcock submits the 

 intended revision of 1898 in which four genera with fifteen species are removed from 

 the Dinosauria and are placed once more with the leptodactylous birds which would 

 seem to be rather a retrogressive step in spite of the fact that the word "birds" is 

 preceded by an interrogation point. C. H. Hitchcock ('89b) would call dinosaurs only 

 such as show front feet, heels, or tails. Moreover, he considers birds long legged and 

 dinosaurs short of limb, although short as well as long limbed birds exist, while fHnosaurs 

 as a rule were rather long legged and certainly the great majority of cursorial forms 

 among them were capable of long strides when well under way. 



E. Hitclicock's classification of 1858 divided the forms into the following groups: — 



Group I. — Marsupialoid Animals. 

 Anomoepus, etc., 3 genera. , 



Group II. — Pachydactylous or Thick toed Birds. 

 Brontozoum, Grallator, etc., 3 genera. 



Group III. — Leptodactylous or Narrow toed Birds. 

 1. Tridactylous, — Argozoum, etc. 2. Tetradactylous, — Ornitliopus, etc., 4 genera. 



Group IV. — Orxitiioid Lizards or Batraciiians. 

 Gigantitherium, Plesiornis. etc.. 7 genera. 



Group V. — Lizards. 

 Plectropterna, etc., 11 genera. 



Group VI . — Batrachians. 

 Otozoum, etc., 10 genera. 



Group VII. ClIELONIANS. 



Chelonoides, etc., 5 genera. 



Group VIII. — Fishes. 

 Ptrlichnus, 1 genus. 



