[1] In 1854, another Swiss naturalist, Henri Louis Frédéric de Saussure, set out for an expedition across the West Indies and Mexico, for which he invited Sumichrast.

[2] In April 1855, Sumichrast and the other expedition members arrived in Veracruz, and went to Cordoba where they stayed at Tospam, the estate of entomologist Auguste Sallé, who was setting off to explore the surrounding mountains with Adolphe Boucard.

They stayed only a short time and continued on to other towns of the Mexican interior, including Orizaba, Puebla, Mexico City, and Tampico.

[2] As the expedition became more dangerous, and the war seemed to approach, Saussure became increasingly displeased with Mexico, reporting he wished he had chosen Ecuador instead.

[1] Sumichrast collected many specimens of reptiles, amphibians, birds, mammals, as well as insects, crustaceans, plants, minerals, and fossils.

He had contacts in museums in Mexico, Switzerland, France, and the United States, sending specimens to other scholars including George Newbold Lawrence, Edward Drinker Cope, Matteo Botteri, and Joseph Charles Hippolyte Crosse, as well as Saussure and Boucard.