A Micro-organism associated with Sperm Cells of Ornithodoros

Abstract

DURING an examination of the female genital tract of Ornithodoros tholozani it was noted that sperm contained in spermatophores lying in the uterus have a peculiar form. A detailed examination of the sperm showed that each one is covered with many hundreds of spindle-shaped micro-organisms (Figs. 1 and 2) attached to the posterior third of its broad portion. The systematic position of these micro-organisms is uncertain. They stain vitally with Janus green and methylene blue, and remain alive in saline between slide and cover glass for more than two weeks. Osmium tetroxide and formalin vapours proved to be the best fixatives. Heidenhain hæmatoxylin, safranin after osmium tetroxide, and Giemsa after formalin fixation gave satisfactory staining. The micro-organism is about 15–20µ in length, 1–2µ in width, with pointed ends (Fig. 3). No flagellum was observed.