Fig. 4

Transparent flexible models and fluid dynamics tests (first pumping movement, outflow) using the Agelastica alni spermatheca models. With a realistic internal protuberance (left column) and without the protuberance (right column). a-a’ The models fully immersed in 1,2-propanediol. b-b’ Sudan Red in 1,2-propanediol was injected. c-e’ The first pumping cycle performed was filmed at 50 fps, and still images showing different stages are exhibited. The solid white arrows indicate directions of the C-arm movement. The black arrows show a marked shift of the injected ink spots in the models. f-f’ Schemes of the observed outflow in the first pumping cycle. Transparent flexible models and fluid dynamics tests (inflow) using the Agelastica alni spermatheca models. With a realistic internal protuberance (left column, highlighted with red dashed lines) and without the protuberance (right column). g-i’ The first pumping filmed at 50 fps (g-g’: while pulling back the C-arm, h-h’: just after finishing pulling back the C-arm, i-i’: just before the second pumping cycle started), and still images showing different stages are presented. The solid white arrows show the direction of the distal C-arm movement. The black arrows show a marked shift of the fluid in the models. j-j’ The inflow at the end of the 5th pumping cycle. k-k’ Schemes of the observed inflow during the first five pumping cycles. The light-pink circles in the schemes indicate the original locations of the injected ink