a Piich>/j)o(i from f/ir Cambridge Upj>er (rreeiisand. ',\\') 



liglit on tin- 1 >iiiosaurian artiiiitics attributable to direct de- 

 scent, but only demonstrates in the livint; reptiles collateral 

 divergences tnun t'ossil ty|H's wliieli have still to be discovered. 



But one plialan«^e was t'oimd with the nieta[)odiuui ; it, too, 

 recalls the phalange of an elej)hant, beini,^ like the second in 

 the compression of the distal articulation from above down- 

 ward, and in the shortness of the bone from front to back. As 

 preserveil, the proximal articulation measures 1^ inch from 

 side to side, while the distal articulation measures 1^ inch 

 from side to side. The posterior articulation is transversely 

 ovate, slightly concave, and, as preserved, measures an inch 

 from above downward in the middle ; but both articulations 

 are worn ; the distal articulation does not measm*e f of an inch 

 from above downward. Tiie bone is more compressed on its 

 right side than on the left ; and the right measures less from 

 front to back than the left side, the right side being 1^ inch, 

 and the left about an eighth of an inch more. Among reptiles 

 only Chelonians have phalanges of this shape. 



The vertebra} associated with these foot-bones are all caudal. 

 The earliest in sequence of the series preserved may be re- 

 garded as one of the earlier caudals ; for relatively to the others 

 the centrum is shorter and dee])er, the transverse process and 

 neural arch (which is not jn-escrved) had a stronger attach- 

 ment, and the facets for the chevron bone on the hinder mar- 

 gin were wider apart and larger. The anterior articulation is 

 the more concave of the two, and has a central boss similar to 

 that seen in Pliosaurs and certain Plesiosaurs. The outline 

 of tlie posterior end of the centrum is a depressed pentagon, 

 measuring about 2| inches from above, and more than 2^ 

 from side to side Avhere widest. l''rom front to back the 

 centrum nieasiu*es 2 inches. 



The second bone of the series is in much better preserva- 

 tion : it measures 2j inches in length ; and the posterior arti- 

 culation is not so much larger than the anterior articulation. 

 The neural arch is not preserved ; but tlie broken attachment 

 of the neurapophysis is lenticular, about an inch huig and a 

 \ of an inch wide, and placed equally distant from the anterior 

 and posterior margins. The space between the neuraj)o])liyses 

 is concave and a little excavated. External to the neural arch 

 on the shoulder of the centrum on each side is a prominent 

 ridge, which arises about f of an inch from the anterior mar- 

 gin (where they are If inch apart) ; they are prolonged hori- 

 zontally backward, becoming rather more marked and slightly 

 diverging ; they make the lateral spaces both above and bcloAv 

 them to be concave. Rather lower below this pair of ridges 

 than they are below the neural arch is a second horizontal 



24^ 



