STUDIES ON SPERMATHECAL FILLING IN AEDES AEGYPTI (LINNAEUS). II. EXPERIMENTAL

Abstract

Spermathecal filling in this mosquito (1) is not affected by changing the position of the female, (2) is not affected by crushing the head of the female during or immediately after forced mating, (3) occurs in the freshly isolated female terminalium, and (4) even occurs in some saline whole mounts containing the bursa, vagina, and spermathecal complex (i.e., will occur in vitro, although rarely). (5) Spermathecal filling can occur in females immobilized by exposure to nitrogen, ether, CO2, cyclopropane, and during submergence in an ice-water bath at 4 to 7[degree]C. When seminal vesicle sperm were injected into the bursae of virgins, very few of them reached the thecae (18.3% "takes"). When ejaculates were removed from freshly inseminated females and injected into the bursae of virgins, womewhat better results were obtained (35.7% "takes"). Evidence is presented that the behavior of the sperm alone cannot adequately explain how they leave the non-muscular bursa, make a sharp U-turn, ascend non-contracting ducts and quickly fill spherical reservoirs which lack muscles. It is not clear what role the female plays during spermathecal filling.