1897.] Recent Literature. 315 
paper by Van Bemmelen on the Phylogeny of Tortoises read before 
the Zoological Congress of Leyden. In this review Baur shows that 
Van Bemmelen has fallen into a good many errors of interpretation 
based on embryologic grounds, and presents a sketch of what is no 
doubt the correct phylogeny of the order Testudinata. The two papers 
constitute an excellent commentary on the necessity of interpreting em- 
bryologic data by the facts of paleontology. An appendix discusses 
briefly the characters of the Otocelid family of the Cotylosauria, 
which the reviewer has regarded as the Permian ancestor of the tor- 
toises (Proc. Amer. Philos. Soc., 1896, p. 122). Baur does not consider 
this proposition to be proven. He observes that the element which I 
have called clavicle includes both clavicle and cleithrum, but produces 
no evidence to support such a view. Were Otoccelus a Stegocephal, 
his idea might be probable, although the cleithrum is not distinctly 
visible in the Stegocephal Eryops; but as the former genus is a Coty- 
losaurian, i. e., a reptile, itis highly improbable, as no reptile is known 
to possess this element. He also remarks that the possession of a car- 
apace means “gar nichts” in this connection. When, however, we 
read (p. 557) that “ the characteristic of the tortoises is the carapace” 
it is evident that the words “ gar nichts” are much too emphatic. In- 
deed the possession of a carapace is the essential of an ancestor of the 
Testudinata, since the Triassic forms possess one already well devel- 
oped, as Baur has the merit of showing. 
In the second paper Dr. Baur in connection with Mr. E. C. Case, 
describes the best preserved skull of Dimetrodon yet obtained. The 
authors add some important points to the osteology of the Pelycosaurian 
skull, but curiously enough do not refer to the anticipation of many of 
their results in the description and figure of the nearly allied genus 
Naosaurus published by the reviewer in the year 1892 (Trans. 
Amer. Philos. Soc., p. 14, pl. II, figs. 7, Ta). They add to what is 
there stated the description of the bones of the preorbital region, and 
determine the entire distinctness of the supramastoid (“ squamosal ”) 
Ueber den Wirbelbau b. d. Reptilien u. e. a. a ca saga von A, Gitte; 
Zeitschrift f. Wissensch. Zoologie, LXII, 3, 1896. Leipzi 
Psittacotherium, a Member of a New and Primitive kois of Edentata, by 
Dr. J. L. Wortman. From the Bulletin of the Amer. Mus. Nat. History New 
York, Nov., 1896, p. 259. The Ganodonta and their relation to the Edentata, by 
a Wertman, M. D., loc. cit. pp. 59-1896. 
The Stylinodontia, a Suborder of Eocene = by O. ©. Marsh, Amer. 
Journ. Sci. Arts, 1897, Feb., p. 137. New Hay 
Contributions from the Zoological Labowatery of the University of 
Pennsylvania, No. VII. 
