Oct.1rgo1. THE Fore Lec or Morosaurus—RiIcocs. 281 
NOTE ON THE GENUS CAMAROSAURUS, COPE. 
While examining the type specimen of Camarosaurus at the Ameri- ° | 
can Museum, through the kindness of Dr. Osborn, the writer was 
struck by the similarity of its pectoral girdle to that of Morosaurus. 
This similarity is especially noticeable between the large coraco- 
scapula (Mus. No. 6285) and Cope’s type as figured in Pl. XLII. 
The presence of but four codssified centra in the sacrum offers a 
further basis of correlation. The gap between the two forms, in 
point of size, is now partially bridged by the large specimen just re- 
ferred to, AZ. robustus. Camarosaurus may thus prove to be the ex- 
treme type of development in this phylum; if not, as Dr. Osborn has 
suggested,* a member of that genus. 
However, it is probable that AZzlantosaurus, Marsh, is more 
nearly related to this genus than is Morosaurus. The types of both 
come from the same locality at Cafion City and from nearly the same 
horizon. Their size, as represented by the length of the femora, is 
essentially the same. Each has four codssified centra in the sacrum; 
those of the Cope specimen are described as solid, while the New 
Haven specimen is nearly so. A third sacrum in the collection of this 
Museum, provisionally referred to Atlantosaurus,t has the same verte- 
bral formula, is similar in relative size and has only very small cavities 
in the centra. The coracoid of the Museum specimen is similar to 
that of the type, though slightly larger, as is the specimen through- 
out. The characters of the first caudal, especially the short blunt 
diapophyses, are characteristic of both. In his original description 
Cope predicted the unusually long humerus which the Museum speci- 
men has so well demonstrated. The three specimens may thus be 
regarded as representatives of a single genus, which, in view of its 
priority, should retain the generic name Camarosaurus. The descrip- 
tion of the type specimen promised by Dr. Osborn will doubtless 
throw further hght upon the relationship of this interesting group. 

* Bull., Am. Mus., Vol. XIV, p. 200. 
{7 Science, April 5, 1901. 
