The word 'germinal' is correct and usable in written English.
It is usually used to describe something that is in its earliest stages of development or growth. For example, you could say: "The formation of our new company was a germinal moment in our success story."
It inspired Emile Zola's 1885 novel "Germinal" about a coal-miners' strike.
He instituted the Civil Code and founded the lycées, the Bank of France, the franc germinal and the metric system.
The germinal epithelium undergoes cell division, however.
The germ (germinal) cells, which eventually give rise to the gametes, are often segregated from the somatic, or body, cells at a very early stage during cleavage and before the subdivision of the embryo into ectoderm, mesoderm, and endoderm.
In humans, cri-du-chat syndrome is caused by a heterozygous deletion at the tip of the short arm of chromosome 5. Infants are born with this condition as the result of a deletion arising in parental germinal tissues or even in sex cells.
Gastrulation and the formation of the three germinal layers is the beginning of the subdivision of the mass of embryonic cells produced by cleavage.
Still another method of rudiment formation in a germinal layer is by the development of local thickenings, elongated or round, and detachment from the epithelial sheet.
Lastly, the cells of a germinal layer may give up their connection to each other and become a mass of loose, freely moving cells called embryonic mesenchyme.
The medulla, which contains no germinal elements, exhibits no significant cyclical activity, is usually inconspicuous, is continuous with the dorsal mesentery, and, in cyclostomes, is hardly distinguishable from the latter.
Immediately after gastrulation and sometimes even while gastrulation is underway the germinal layers begin subdividing into regions that will give rise to various parts of the body.
Spermatogenic cells migrate into the cysts from a permanent germinal layer, which, depending on the species, may lie among cysts at the periphery of the testes or in a ridge along one margin of the testis.
