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Parablast, par′a-blast, n. the supplementary or nutritive yolk of a meroblastic egg or metovum—as distinguished from the archiblast, or formative yolk.—adj.

Latebra, lat′eb-ra, n. the cavity in the food-yolk of a meroblastic ovum.—adj.

Meroblast, mer′ō-blast, n. a meroblastic ovum.—adj.

Such a type of segmentation in which only part of the ovum segments is called meroblastic.

So far, the essential differences between the development of fowl and frog, the meroblastic segmentation, absence of a typical gastrula, and the primitive streak, seem comprehensible on the theory that such differences are due to the presence of an enormous amount of yolk.