The series consists of 31 watercolour paintings of fish, created while Elizabeth Gwillim and Mary Symonds were living in Madras, India (modern-day Chennai). The paintings are preceded by an introductory page of notes by Casey A. Wood. The paintings were originally attributed to Gwillim by Wood, largely on the basis of handwriting, but have more recently been tentatively attributed to Mary Symonds approximately around the year 1805 on the basis of information found in the sisters' correspondence. The fishes depicted are identified by a handwritten caption in the margin of each painting. Approximately one third of the paintings also feature an additional caption written in an Urdu script. These paintings may be copies of Symonds' originals created by a local artist in India. Item 30 (Crocodilus palustris) also contains additional manuscript notes.

The collection contains 164 botanical and zoological paintings created chiefly by Elizabeth Gwillim as well as possibly by her sister Mary Symonds while living in Chennai, India (then Madras). The collection includes 121 watercolours of birds with inscriptions, 31 watercolours of fish, and twelve of flowers, drawn from life rather than specimens. The paintings reflect the sisters' time in Madras during which, as artists and letter writers, they created a substantial visual record of the landscape and inhabitants of Madras and environs. The paintings also reflect Gwillim's scientific pursuits, including her study of botany.