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
2 turtle-mouth drawings (5 x 5 cm. and 5 x 4 cm.)Repository: Ernst Mayr Library, Museum of Comparative Zoology, Harvard UniversityCall number: bAg 168.60.10 (21)i
Drawing of turtle and head (7 x 18 cm., 3 x 5 cm.)Repository: Ernst Mayr Library, Museum of Comparative Zoology, Harvard UniversityCall number: bAg 168.60.10 (23)f