The rudimentary thorax presents traces of a division into three segments; and the dorso-lateral margins of the cephalic blastoderm, behind the procephalic lobes, have a sinuous margin.
"On the Origin and Metamorphoses of Insects"
Sir John Lubbock
Where, as with lower creatures which do not lay up large stores of nutriment with the germs of their offspring, the inner mass is inconsiderable, the outer layer of cells, which are presently made quite small by repeated subdivisions, forms a membrane extending over the whole surface-the blastoderm.
"Essays: Scientific, Political, & Speculative, Vol. I"
Herbert Spencer
This will represent the blastoderm.
"Essays: Scientific, Political, & Speculative, Vol. I"
Herbert Spencer