Fine structure of egg envelopes and the activation changes of cortical alveoli in the river lamprey, Lampetra fluviatilis.
D000818:Animals; D005321:Extraembryonic Membranes / Q000033:anatomy & histology; D005260:Female; D005306:Fertilization; D005399:Fishes / Q000033:anatomy & histology*; D008297:Male; D008566:Membranes; D008854:Microscopy, Electron; D010063:Ovum / Q000166:cytology*