February 24, 1905.] 



SCIENCE. 



297 



the top of the skull. The Astrapotheria 

 stand apart in the enlargement of the 

 canines, showing analogies with the Amy- 

 nodonticliP, which are, however, deceptive. 

 Like the Litopterna they lack the auditory 

 expansion. All these ungulates are fur- 

 ther distinguished by being entirely horn- 

 less. 



Dr. 0. P. Hay read a paper 'On the 

 Group of Fossil Turtles known as the 

 Araphichelydia.' The author's studies are 

 based on a very complete skeleton of the 

 Jurassic Compsemys plicahda in the Amer- 

 ican Museum and several fine specimens of 

 Baena, collected in the Bridger beds of 

 "Wyoming. In the members of this super- 

 family the temporal region is roofed in, 

 there are nasals and a lachrymal bone; the 

 pterygoids exclude the quadrate from con- 

 tact with the basisphenoid ; the cervical 

 vertebrte may be biconcave or one or both 

 ends may be convex ; the neck short and 

 adapted for motion in all planes, but more 

 like that of the Pleurodira; the pelvis not 

 suturally articulated with the shell. The 

 group has evidently given origin to the 

 Cryptodira and the Pleurodira, the former 

 retaining the skull structure, the latter 

 group retaining the neck and shell struc- 

 tures. 



Papers were also read by Mr. W. J. Sin- 

 clair on 'The Marsupials of the Santa Cruz 

 Formation'; by Dr. Wm. Patten, 'On the 

 Structure of the Ostracoderms' ; by Dr. M. 

 S. Farr, 'On Mammals from the Fort 

 Union Beds.' 



Professor Wm. Patten described the 

 structure of Botliriolepis, based on the 

 study of a large number of well-presei'ved 

 specimens recently obtained by him in New 

 Brunswick. Many specimens were ex- 

 hibited which illustrated and confirmed the 

 most important features of the description. 

 The struetui-e of the mouth parts, the posi- 

 tion of the gills, anus, anal fin and other 

 organs indicate that the Ostracoderms must 



be separated from all other known sub- 

 divisions of the Chordata and raised to 

 the dignity of a separate class. 



Professor S. W. AVilliston reported on an 

 important new locality for Triassic verte- 

 brates on the east side of the Wind River 

 range, near Lander, Wyo., yielding the 

 most important remains which have yet 

 been found in the American Triassic. The 

 collections, which as yet have not been pre- 

 pared and studied, represent four great 

 groiips. as fdh'vrs: The Tjabyrinthodontia 

 are represented by very large forms allied 

 to Mctoposaurtis, of Wui'temberg, but gen- 

 erically distinct from it. TheDicynodontia, 

 or Anomodontia, hei-etofore not rei)resented 

 in America, are apparently represented in 

 portions of a skeleton, including a humerus 

 resembling that of Flatypodosaurus, and 

 a pelvis remotely suggesting that of 

 Tapinoccphalus. The teeth named Palceoc- 

 tontis by Cope and referred to a dinosaur, 

 probably belong to members of this group, 

 the affinities of which still require further 

 study. The third group is widely distinct, 

 including an animal with a slender hu- 

 merus, a scapulo-coracoid with very promi- 

 nent glenoid fossa, the blade of the scapula 

 being placed at right angles to the lower 

 portion of the arch, the humerus without 

 entepicondylar foramen; the resemblances 

 are rather with the Pterosauria than any 

 other group. The fourth great group is 

 the Phytosauria; here no less than four 

 skulls of the Belodontia were found, all 

 different, probably representing four 

 genera, differing in the elongation of the 

 snout and position of the nostrils, and 

 adding substantially to our knowledge of 

 this group. The author incidentally re- 

 marked that he had positively determined 

 that the Hallopus Beds near Canon City, 

 Colorado, are of Triassic and not Jurassic 

 age; these beds contain labyrinthodonts 

 and crocodiles which belong to a higher 

 horizon than that discovered near Lander. 



