1907

The 1907 Cornellian has pages for 26 residential social fraternities with houses.  There were four sororities listed,  all in Sage Hall,  which is what I think Kappa Alpha Theta (Cornell's first sorority) had in mind when they took this photo for their website with Sage Hall in the background. 

https://www.cornellsun.com/article/2019/11/solar-flashback-its-all-greek-to-me-a-history-of-greek-life-policies-at-cornell

1. Zeta Psi  - 415 Stewart

2. Chi Phi - Edgemoor

3. Kappa Alpha - College

4. Phi Kappa Psi - McGraw Place

5. Alpha Delta Phi - Stewart

6. Delta Upsilon - South Avenue

7. Chi Psi - University Avenue

8. Theta Delta Chi - South Avenue

9. Delta Kappa Epsilon - South Avenue

10. Phi Delta Theta - Edgemoor

11. Psi Upsilon - Central

12. Beta Theta Pi - South Avenue

13. Alpha Tau Omega - University

14. Phi Gamma Delta - 603 E. Seneca

15. Phi Sigma Kappa - University

16. Delta Tau Delta - Edgemoor

17. Sigma Phi - Central 

18. Sigma Chi - Stewart

19.  Delta Chi - 503 East Buffalo

20. Sigma Alpha Epsilon - Stewart

21. Delta Phi - Zodiac - Stewart

22. Kappa Sigma - University

23.  Alpha Zeta - 70 Thurston

24. Sigma Nu - 111 Stewart

25.  Theta Xi - 717 East Buffalo

26.  Seal & Serpent - 105 Highland Place

The 1907 map but not the yearbook shows the Theta Lambda Phi (1903-1912) house on Edgemoor Lane.  They would become Sigma Phi Epsilon and use the same house.   The map also shows Cerberus (1904-1911) at 303 Eddy Street which became Phi Kappa Sigma.   So there appear to have been a total of 28 social fraternities on campus at this time.