Ampullaria, one of the Apple Shells. (o) operculum; (s) respiratory tube.
H. Alleyne Nicholson, An Introductory Text-book of Zoology(Edinburgh:William Blackwood and Sons, 1971) 102
2400×1429, 3.3 MiB
1024×609, 92.5 KiB
640×381, 40.8 KiB
320×190, 12.1 KiB