210 li. S. Lull — Fossil Dolphin from California. 



The slab was found on the Suey ranch, owned by the .iSTew- 

 hall Laud and Farming Company, in San Louis Obispo county, 

 California, in what is called " Sulphur Creek " canyon, about 

 700 feet above sea-level and 30 miles in a direct line from the 

 ocean. According to the company's maps, the place is in the 

 southeast corner of Section 17, Range 32, West Township 11, 

 north San Bernardino Base and Meridian. Sulphur creek 

 empties into the Santa Maria river at about the southern 

 extremities of Sections 16 and 17, and Mr. Newhall found the 

 specimen about a quarter of a mile up the creek. 



The fossil is presumed to be of Miocene age, judging from 

 the Geologic Map of North America published in 1911. The 

 precise level, however, has not been determined, but is at 

 present under investigation through the courtesy of Professor 

 John C. Merriam, of the University of California. 



Extent and preservation of the specimen. 



The specimen, which bears the catalogue number 10040, 

 Yale Museum fossil vertebrate collection, consists of a single 

 slab of sandstone, upon the surface of which the articulated 

 skeleton of the dolphin was impressed (see Plate YIII). Most 

 of the bones have been eroded away, so that their imprints 

 alone remain, with but little of the osseous material clinging 

 to their depths. Of the skull, however, a great deal was pre- 

 served, for, while the exposed surface had suffered from weath- 

 ering, removal of the matrix from the reverse side displayed 

 most of the right aspect of the cranium and jaws. 



There remains of the animal, therefore, the entire skull and 

 jaws with many of the teeth, some entire, some having but the 

 root embedded in the alveolus, and others represented only by 

 their imprint in the matrix. The vertebral column is indi- 

 cated as far as the twelfth dorsal, though each bone cannot be 

 clearly distinguished. There are twelve pairs of ribs and the 

 impression of the sternum is distinct. Of the limbs, the left 

 scapula, the humerus, and the ulna are represented, and at 

 least four phalanges of the second or third digit, while of the 

 right paddle, impressions of all the elements remain except the 

 distal ends of the several digits. There is unfortunately no 

 trace of lumbar or caudal vertebrae, nor have I recognized any 

 portion of the pelvis, which would be of great interest in so 

 old a form. I should judge the animal to be fully adult 

 despite its rather small size, as the bones show scarcely a trace 

 of the epiphyses. 



The only preparation for study necessary was the removal 

 of the matrix from the right aspect of the skull, and, after a 

 careful preliminary examination, it was deemed expedient to 



