462 0. C. Marsh—sStructure of Mosasauroid Reptiles. 
The humerus is very small and slender, and moderatel 
stricted in the middle. The deltoid crest is ae bya 
round articular tubercle, separated from the head bya deep 
a The distal end is somewhat broader than the head, and 
has a well-developed posterior process, and is Sat distally, 
The cervical vertebree have the articular faces but slightly 
transverse, with a faint superior emargination. The anterior 
dorsals are subcordate at their extremities, and the pee 
dorsals have their articulations still more depressed. ‘The ca 
dals are elevated, and have the chevrons artic 
Measurements. 
Length of Sa border of maxillary,........++++ 320° “ 
Depth of maxillary at anterior nareal expanse,......-+-+ 44° 
Space pegied by ieave anterior teeth in mandible,. . . 205° 
Anterior extent of mandible beyond center of first tooth,. 32° 
Depth of mandible under first to es » Heb ds S45 e ee 30° 
Extent of seven anterior palatine teeth,........+..- Feet 
Transverse diameter of ancoouioieal i on condyle, rucensaee 54° 
OOD CINE oi ck ech ss cae eb ae Cee oe snes 
Length of basioccipital, tide Peis Gade es sae eee ate 69° 
OF WUROPR is Ss bas oh i ee A Uevue eeere 81° 
Transverse diameter of distal. ond, .4..0i00 0555-0 meme 44° 
Antero-posterior diameter, ........ ...++- had eee 19° 
Length of pesos Ook, «59 ) ln dy abe e sis ue Whty a4 me 43 
BTC Gr OMOEA os cs pa vc SV as oy beeps e seme ? 
Greatest Sawer of wae OMG, «ao 0 os < cious nee oem 44° 
Greatest diameter of Mintel end; cs save 0s » SO EEE 57° 
Maen OF Wenn 2k A ys wp 0s oo ase eee 106° 
en Se of axis with odontoid PTOCESS,... 2c ee ce eeeceee 68° 
Length of centrum of axis... .. 0.000 cane sv eewnenneoes 44° 
Vertical diameter of articular i | Rg eases ear olau cde orias 34° 
Transverse diameter, .........0.cee500 eR cae 
Length of proximal caudal, Oo is okt eda a oe 
Vertical diameter: of ball, 225 10..% 5.0 voi s esc tose ee 
Pranéverse diametet. ..¢ii0. 5,600. 04505s' Tevanceesee Vie 
It is only necessary to compare this species with Laodon crass: 
artus and Liodon proriger, both described by. Prof, Cope. ks 
se ws foun the writer, in Jul last, on the a ae eof the 
ey Hl iver, in Kansas. The geological horizon is the 
ee ale of the upper Cretaceous. 
