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and thrown forward; nasals forming side of h-ood posteriorly but separated 
by upper limbs of premaxillse; posterior spike inceptive; orbit and lateral 
temporal fossa large; slit above narial passage open well back; maxilla 
massive; fore limb massive; anterior blade of ilium thick, posterior blade 
broad; pubis broad anteriorly, postpubis large; ischium massive, foot-like 
expansion only moderately developed; femur short; ossified tendons 
extending down in front of femur and Over knee. 
SKULL 
When compared with the type of L. lambei this skull is very massive 
and the spike which is such a prominent feature in the genotype is only 
in the initial stage of development. A second skull in our collections 
(Cat. No. 8631), which is comparable in every way with the specimen 
chosen as the type of the new species, possesses a slightly longer, but still 
inceptive spike. The possession of a fully developed spike in the type, 
which is small, and in a large skull in the collections of the Royal Ontario 
Museum, seems to show that this cannot be regarded as an age or individual 
variation. 
The crest is relatively lower than in L. lambei and the lower limb of the 
premaxilla is more strongly swollen and the superior edge bent forward. It 
has not been possible to work out the narial passage in detail, but it enters 
the hood through the lower limb of the premaxilla, but farther forward 
than in L, lambei. In this species the upper limb of the premaxilla is 
not so strongly developed posteriorly as in L. lambei , but the united 
bones divide the nasals to their posterior extremity. The posterior end of 
the lower limb of the premaxilla extends back to beyond the centre of the 
orbit. The diagonal groove that crosses the lower limb enters the air 
chamber near its base. 
The nasal is broader and occupies a more prominent position on the 
side of the hood than in L. lambei and appears to have flanked the air 
chamber. There is a moderate-sized opening between the antero-superior 
edge of the nasal and the upturned lower limb of the premaxilla, but this 
is partly covered by fingering of bone from the premaxilla. This seems to 
show conclusively that the openings in the hood represent undeveloped or 
unossified portions of the bones. 
The prefrontal is small and bounds only half of the superior border of 
the orbit. 
The lachrymal is weak and situated well down on the anterior rim 
of the orbit, but it sends a long, slender tongue of bone up to meet the tip 
of the prefrontal and just cuts off the premaxilla from taking part in the 
formation of the orbital rim. Thus the lachrymal, in spite of its slender- 
ness, forms the greater part of the anterior border of the orbit. 
The orbit and postorbital vacuity are very large. The postorbital bar 
is slender. 
The maxilla is massive and convex antero-posteriorly on the superior 
face of its forward half. It is rather broad superiorly to accommodate 
the swollen lower limb of the premaxilla. There are 39 or 40 vertical 
rows of teeth. 
