Increase in size following emergence from hibernation may be due in part to proliferation of the sustentacular cytoplasm.
Sperm are present in small groups within the sustentacular cytoplasm, but ordinarily are absent in the lumina.
The sustentacular cytoplasm has a less compact arrangement in late May than in April.
The lumina are filled with cellular detritus and are no longer bordered by a clear ring of sustentacular cytoplasm.
sustentacular sus·ten·tac·u·lar (sŭs'tən-tāk'yə-lər, -těn-)
Serving to support.