Notices of Memoirs — E. T. Newton on Gastornis. 363 



These gigantic bird-bones were obtained from the "Blue Clay" 

 and lignite patches of the Woolwich Beds, which lie immediately 

 above the " Mottled Clays," and are marked / and gf in Mr. Klaassen's 

 section. The most interesting among these specimens are the portions 

 of two large tibiotarsi and parts of a femur. The most perfect 

 tibiotarsus when complete must have had a length of at least twenty 

 inches, and its trochlear extremity is three inches and a half wide. 

 Of the second tibiotarsus only the lower end is preserved, but this 

 is larger, being a little over four inches wide. These bones resemble 

 very closely the corresponding parts of Gastornis Parisiensis, but 

 present differences sufficient to prevent their being referred to the 

 same species, and they have therefore been named after their dis- 

 coverer, Gastornis Klaassenii. This Eocene bird must have been 

 as large and heavy in build as the Dinornis crassus of New Zealand. 



The original specimen of Gastornis from the Lower Eocene beds 

 of Meudon near Paris, was described by M. Hebert in the Comptes 

 Eendus for 1855 (vol. xv. pp. 579 and 1214), and the genus named 

 after their discoverer, M. Gaston. These Parisian bird-remains were 

 afterwards more fully described and compared with recent forms by 

 Prof, (now Sir Eichard) Owen, in the Quarterly Journal of the 

 Geological Society (vol. xii. p. 204, 1856), and by M. Milne- 

 Edwards (Oiseaux Fossiles, vol. i. p. 165). Unfortunately the troch- 

 lear extremity of the tibiotarsus of G. Parisiensis was so badly pre- 

 served as to render the comparison most difficult and unsatisfactory. 

 Other specimens referable to the same genus have since been dis- 

 covered in Lower Eocene beds near Eheims, and described by Dr. 

 Victor Lemoine under the name of Gastornis Edwardsii (Eecher. 

 Oiseaux Foss. envir. d. Eeims, 1878 and 1881) ; these include parts 

 of the head, vertebra, etc., and are therefore extremely valuable ; 

 but the lower ends of the tibiotarsi are far from being well pre- 

 served, and consequently do not help us much in comparing this 

 most important bone with the same parts in recent birds. Mr. L. 

 Dollo, of the Brussels Museum, has described the distal end of the 

 femur of a large bird which he has referred to Gastornis Edtoardsii, 

 Lemoine, from the Lower Landenien of Mesvin, near Mons, 

 Belgium (Bull. Mus. Eoy. Hist. Nat. Belg. torn. ii. p. 297, pi. xi. 1883). 



These large tibiotarsi from Croydon have their distal ends so 

 perfect that every detail of their structure can be studied. It is not 

 a little remarkable that, in this part of its organization, Gastornis is 

 quite unlike any of the large birds, recent or fossil, at present known ; 

 the living Eatitge having a tibiotarsus quite unlike that of Gastornis ; 

 and that of Dinornis, although making a somewhat nearer approach, 

 has the trochlear extremity of an entirely different type. Indeed, the 

 known forms of Eatitse all differ more from Gastornis, in regard to 

 the tibiotarsus, than do some of the living Carinatje; and it is 

 interesting to find that opinions, expressed by some previous writers, 

 as to the Anserine affinities of Gastornis, are confirmed by the 

 detailed comparison with recent forms, which the more perfect 

 Croydon specimens now render possible. Although the tibiotarsus 

 of Gastornis Klaasseni more nearly resembles that of the Anserine 



