Fig. 3. (A) Ventral and (B) side views of the scaled model (40:1) of the midsection of the lateral flagellum of the antennule of a P. argus. The distal end of the antennule is to the left, and proximal end is to the right in the image. The guard hairs and aesthetascs were made from Pyrex© glass to match the index of refraction of mineral oil used as the viscous fluid in the towing tank. The lateral flagellum of the antennule to which the hairs were attached was fabricated using Sculpy© modeling compound.