2 turtle drawings (9 x 14 cm. and 9 x 13 cm.)Repository: Ernst Mayr Library, Museum of Comparative Zoology, Harvard UniversityCall number: bAg 168.60.10 (18)e
2 turtle-head drawings (5 x 5 cm. and 4 x 7 cm.)Repository: Ernst Mayr Library, Museum of Comparative Zoology, Harvard UniversityCall number: bAg 168.60.10 (21)h