14 FigeLp CotumMBian MusrtuM—GEOobocy, Vou. II. 
length. The neck in life must have been thick and heavy at the base, 
tapering rapidly from the trunk to the head. The trunk was broad, 
as is evident from the position of the ribs, with the under side not flat, 
as might be supposed, but strongly convex from side to side. The 
abdominal region proper, between the girdles, must have been short, 
and could not have been very distensible. The short tail was thick atits 
base, as is conclusively shown by the attachment of the ilia and the 
elongated ischia. Furthermore, the fore legs, at least, must have 
been enclosed for a considerable distance at their attachment by the 
skin and muscles of the pectoral region; they could not have been 
pedunculated to the extent that they are usually represented to be in 
the restorations. The species was named in honor of Prof. H. F. 
- Osborn of Columbia University. 
The distinguishing characters, both family and generic, may be 
summed up as follows: 
DOoLICHORHYNCHOPS.—//ead elongate, the facialregion much attenuated; 
teeth nearly uniform in size, small; prefrontal and postfrontal bones not 
joined; partetals extending into a high crest, supraoccipital bones separated; 
znternal nares small, included between the vomer and palatine only; pala- 
tines broadly separated throughout, a large vacuity between the pleryvgoids 
antertorly,; quadrate process of plerygotds short. Neck but little longer 
than the head, composed of nineteen or twenty vertebrae; all presacral 
vertebra of nearly equal length, moderately concave, and with vascular 
foramina below; spines short, uniform in length; diapophyses of the dorsal 
vertebrae situated high up. Coracotds with long epicoracoid process; 
clavicles and scapule free; episternum with an emargination in front and 
behind, the latter forming part of a large tinterclavicular foramen. 
Three eptpodtial bones, all broader than long. TLschium elongated. 
Length ten feet. 
Skutt.—The skull of Dolichorhynchops osborni is of a remarkably 
elongate and slender form, attenuated in front of the orbits, and witha 
thin, high, parietal crest. The region between the eyes is very nar- 
row, the superior temporal vacuities large, and the teeth numerous 
and slender. The head is more nearly of the typical aquatic fish-eat- 
ing type than is perhaps known in any other plesiosaur, and the neck 
is as short as or shorter than in any other plesiosaur hitherto 
described. The skull, as received, was lying partly upon its left side, 
with a part of the right side separated and injured, some of the bones 
having been macerated away. The specimen was completely removed 
from the matrix, including even that which was between the bones, 
and the elements of the brain case were separated out. In conse- 
