Philip Reese Uhler was born on June 2, 1835, in Baltimore, Maryland.

He was an American librarian, educator, and entomologist. He began collecting insects at the family farm near Reisterstown. He attended the private Latin School in Baltimore and Baltimore College. After leaving school, he spent several years as a clerk in his father's store. Uhler preferred to spend his time studying geology, botany, and entomology. He started publishing papers on the insect order Hemiptera (true bugs) in 1856. In 1861, he was appointed assistant librarian of Peabody Institute, and he began his studies at Harvard University as a student of Louis Agassiz. In 1864, Agassiz appointed Uhler to serve as both librarian at the Museum of Comparative Zoology and curator of the museum's insect collections. Uhler also taught entomology at Harvard and lectured at the museum. He attended the Lawrence Scientific School at Harvard and studied with some of the university's most notable scientists and naturalists. Uhler returned to Baltimore in 1867, resuming his position as assistant librarian at the Peabody Institute and, in 1870, he was appointed librarian, a position he held for the rest of his life. He was also actively involved in the formation of Johns Hopkins University and, in 1876, he became one of its first associate professors. He was a Fellow of the American Association for the Advancement of Science, founder and president of the Maryland Academy of Science, and member of the American Entomological Society, Academy of Natural Sciences of Philadelphia, Entomological Society of Washington, and the Royal Society of the Arts (London). Throughout his career, Uhler identified about 600 new species of insects and published numerous notable papers in his field of study.

In 1867, he married Sophia Werdebaugh (c.1835-1884), and in 1886, he remarried Pearl Daniels (1859–1947). He died on October 21, 1913, in Baltimore, Maryland.

Philip Thomas Tyson was born on June 23, 1799, in Baltimore, Maryland.

He was an American chemist and geologist. He came from a well-known Tyson family of Quaker industrialists. In 1837, he became one of two vice presidents of the Maryland Academy of Science and Literature, an organization that has evolved into the Maryland Science Center. Tyson contributed numerous articles on the minerals of the state of Maryland to various scientific journals while living in Baltimore, where he also ran a pharmacy business. In 1830, he entered a partnership with William R. Fisher as Tyson & Fisher, a Drug and Apothecary business. In 1836, this partnership dissolved, and Tyson devoted himself to the practical application of mineralogy and chemistry. Around 1839 he served as the Superintendent of the George's Creek Coal and Iron Furnace. He surveyed California in 1849 and produced the first regional map with geologic notations and several rough topographic/geologic cross-sections. In 1851, he published the book "Geology and Industrial Resources of California." Tyson served as a Maryland State Agricultural Chemist from 1858 to 1862. In 1858, he discovered the fossilized teeth of a dinosaur in Muirkirk, Maryland. This was the first discovery of dinosaur fossils in Maryland, and the species, Astrodonjohnstoni, became the Maryland State Dinosaur in 1998.

In 1824, he married Rebecca Webster (c.1800–c.1886). He died on December 16, 1877, in Philadelphia, Pennsylvania.