It is hard to make out what this statue represents or what it actually is. Apparently, it is a panther attacking a horse. There is a sister (or brother) sculpture across the plaza at the base of the other side of the steps which has the same flavor of this one. The statue is also well known, if not better known as Mounted Amazon Attacked by a Panther.
The sculpture is of a bare-breasted female is seated on rearing horse that is caught in the jaws of an attacking panther. The panther has wrapped itself around the horse's neck and the horse is rearing back on its hind legs with its proper right front hoof up in the air. The female figure, wearing her hair pulled up on top of her head, is seated back on the horse's hind quarters, holding on to the horse's mane with her proper left hand. In her raised proper right hand she holds a spear poised to drive it into the attaching panther.
I couldn't make out the inscriptions on this thing. I relied on the SIRIS site. (On plinth west face cast into bronze as negative:) SOCIETAS ARTIS CULTORUM BEROL (...illegible transcription)/ INENSIS AERE COLLATO FC/ (On plinth east face applied medallion, cast:) FAIRMOUNT PARK ART ASSOCIATION INC. FEB 2 1872 (decorative elements within circle) (On horse's girth strap buckle, west, in cast:) KISS 1830 signed
The sculptor was August Kiss (1802 - 1865), and the founder, Gorham Manufacturing Company. The sculpture was original modeled in 1837, cast 1929 and installed in the same year. The base is of limestone and of course the statue is of bronze. The sculpture's dimensions are approximately 135 x 120 x 60 inches and the base is approximately 204 inches in height.
The original of "The Amazon" was modeled in Berlin in 1837 and was installed at the front of the National Museum of Berlin in 1843. It stood alone for eighteen years until it was joined by a companion piece, "The Lion Fighter," created by Albert Wolff. Both Kiss and Wolff were students of the famous German sculptor, Christian Rauch. In 1889 the Fairmount Park Art Association acquired the original plaster casts of both pieces and displayed them at Memorial Hall. The plaster of "The Amazon" had deteriorated significantly and in 1893 the German government agreed to replace this disintegrating plaster with a new plaster cast from the Berlin bronze. The new plaster of "The Amazon" was exhibited at the Pennsylvania Museum until 1909, when the Art Association decided it would commission only American art works. The plaster was then given to Harvard's new Germanic Museum. However, in 1929 for the new Philadelphia Museum of Art, a bronze cast was made and placed in front of the museum along with a cast of Albert Wolff's companion piece "The Lion Fighter"
Found this on another site. "The Mounted Amazon Attacked by a Panther was the work of German sculptor Auguste Kiss. Caught in the midst of the attack, the figures convey the violence and emotional tension of the moment. The Amazon was installed in 1837 at the steps of the newly built National Museum in Berlin, standing alone for several years until Albert Wolff completed a companion piece, The Lion Fighter. The Fairmount Park Art Association acquired the plaster casts for both works in 1889, but the Amazon cast was in such poor condition that it could not be shipped to the United States.
With the assistance of the German government, a new plaster cast was made from the original bronze and exhibited in Memorial Hall until 1909. The decision to commission only American art prompted the Art Association to present the Amazon as a gift to Harvard's Germanic Museum. However, once construction began on the new building for the Philadelphia Museum of Art, the Art Association arranged to cast another copy so that it could sit across from The Lion Fighter. " SOURCE