Aphrophora quadrangularis (Hemiptera homoptera).
Fig. 237. Resting primary spermatogonium with lobed nucleus.
238. Resting secondary spermatogonium, with nucleus staining much more deeply.
239. Equatorial plate of secondary spermatogonium, 23 chromosomes.
240. First spermatocytes, very early growth stage, x the odd chromosome.
241-243. First spermatocyte, later spireme stages, showing the odd chromosome (x) and a pair of m-chromosomes (m).
244. Similar stage from a safranin-gentian preparation.
245. First spermatocyte, split-spireme stage, x the odd chromosome, m the m-chromosome tetrad.
246. Similar stage from a safranin-gentian preparation.
247-248. First spermatocyte, condensation of chromatin granules to form tetrads in the linin spireme.