NO. 2260. ]^EW RESTORATION OF TRICERAT0P8—GILM0RE. 



109 



Specimen No. 5740 shows that portion of the parietal around the 

 pineal foramen and extending upward above the supraoccipital to 

 have been very thin on the median line. Whether it becomes heavier 

 laterally can not be determined, but higher up it widens perceptibly 

 provided all of the bone is parietal, but it again thins out into a 

 wide sheet of bone that underlaps the dermosupraoccipital as shown 

 in plate 7, P. as has been previously described. 



f^ 



Fr. 



i/^ftf- 



.S.oc, 



\ 



\^S end 



as/).— 



'^\ 



tio.694 



AM. 



"tui.B. oc 



{b's[>.) 



Fig. 5. — Longitudinal section of skull of Diplodocus longus Marsh, No. 694, 

 Ameh. Mds. Nat. History. One-half natural size. B. oc, basioccipital ; 

 B. ft. pk., basipterygoid processes; B. sp., basisphenoid ; car. in., foiiamen fob 



EIGHT CAROTID ARTERY; Ex. OC. EXOCCIPITAL ; F. PIN., PINAL FORAMEN; FR., FRONTAL; 

 0. SP., ORBITOSPHENOID ; Pa., PARIETAL ; PIT. FOS., PITUITARY FOSSA ; PE. OT., 

 PBOOTIC ; ?P. SP., PRESPHENOID ; S. END., SACCUS ENDOLYMPIIATICUS,* S. FC, SUPRA- 

 OCCIPITAL ; TUB. B. OC, BASIOCCIPITAL TUBEROSITY ; I, II, III, IV, V, VI, VII, IX, XI, 

 XII, FORAMINA FOB EXIT OF CORRESPONDING CEPHALIC NERVES. (AFTER OSBORN.) 



In figure 2 S. oc, the supraoccipital is indicated as extending from 

 the top of the foramen magnum to the sutural surface above the 

 foramen for the exit of the IV nerve. Hay in figuring this same 

 specimen ^ regarded only the lower or posterior half as supraoccipital, 



» See Proc U. S. National Museum, vol. 36, 1909, pi. 2, fig. 1, 



