12 
Corythosaurus intermedins Parks 
University of Toronto Studies No. 15, pages 1-57, 1923 
Among the specimens being studied is a well-preserved skull (Plate 
III, figure 2) and partial skeleton (Cat. No. 8704) which, except for size, 
compare closely with the types of C. intermedins Parks (14). The speci- 
men was collected by the writer, in 1919, from the Pale Beds, Belly River 
series, about 3 miles south of the mouth of little Sandhill creek, 210 feet 
above Red Deer river, in Alberta. This locality is very near, and about 15 
feet lower than, that from which the specimen of C. excavatus was collected. 
Only the head, right scapula, forearm, and manus have been prepared. 
The presence of a third specimen, which so closely resembles the 
types of C. intermedins and shows the same variation when compared 
with other species of the genus, seems to verify the establishment of this 
species. The main differences between this specimen (Cat. No. 8704) and 
the one of C. excavatus , previously discussed, are: steeper facial slope, 
posterior closing of the slit above the narial passage, union of posterior 
tip of lower limb of premaxilla and nasals, much higher hood and higher 
nasal, greater number of teeth, more decurved dentary, and longer forearm. 
The posterior closing of the narial slit is the result of expansion of the 
superior edge of the premaxilla. In this respect it more closely resembles 
C. casuarius (1, Plate XLI) than C. excavatus. The broadening of the 
premaxilla is slightly more advanced than in C. excavatus. This would sug- 
gest that the narial passage enters the upper limb of the premaxilla 
slightly farther ahead in this species, but this cannot be definitely stated 
since it is not possible to work out the narial passage in detail. The 
diagonal groove is strongly developed. The foramina, shown by Parks, 
through the upper and lower limbs of the premaxilla, are not present in this 
specimen and there is no spike on the postero-inferior edge of the nasals, 
but these features are not here regarded as of specific importance. The 
lower limb of the premaxilla is strongly swollen, thus forming a buttress 
in front of the eye which must have obstructed the anterior view. The 
nasal is short, very high, and broadly swollen infero-posterioriy. The 
broadly expanded lower part of the nasal along with the swollen lower limb 
of the premaxilla suggest a large subsidiary air chamber. 
The maxilla and dentary are similar to those of the types. There are 
44 vertical rows of teeth in the maxilla and 39 in the dentary. 
The forearm is very long and slender. When compared with the 
fore limb of Lambeosaurus (Cat. No. 8703) this slenderness is very 
noticeable, for whereas the bones are of subequal length, in Lambeosaurus 
they are very much more massive (See table of comparative measure- 
ments) . 
Tetragonosatjeits Parks 
University of Toronto Studies No. 31, pages 1-11, 1931 
Tetragonosaurus seems to resemble Corythosaurus more closely than 
Lambeosaurus , but the smaller size, long slender nasal, low forwardly placed 
dome or hood, development of the upper limb of the premaxilla backward 
to overlap nasal, and less steeply placed cranium seem to justify its 
