SCALES OF THE BUTTERFLY AMATHUSIA HORSFIELDII (The Palmking butterfly of Indonesia)

SLIDE: By Edmund Wheeler, c. 19th C.

This scale was suggested as a test object by Quekett in his Practical Treatise on the use of the microscope in the 1855 third edition. He suggested that a high power oil immersion objective was needed to resolve the cross striations which he called beading but these cross striations are visible even with a 10X n.a. 0.30 objective today. I wonder if he even tried a lower power objective, since other scales often required higher n.a. objectives. In any case it was not mentioned in the brief reviews of Test objects listed in the Micrographic Dictionary or in the 1854 edition of Hogg's The Microscope, Its history, contruction and teachings of 1854, nor was it mentioned in the more comprehensive discussion of test objects in Spitta, Microscopy The construction Theory and the use of the microscope of 1920.

A. horsfieldii 10X objective brightfield transmitted light illumination:

A. horsfieldii 40X brightfield transmitted light illumination: