neurulan.

1878 Amer. Naturalist 12 642 It treats of the origin and growth of the egg, its impregnation and mode of deposition, of the changes preliminary to and during cleavage, of the gastrula and ‘neurula’ stages, comprising the growth of the germ-layer and the concomitant invagination of the pharyngeal clefts, of the origin of the nerve-chain, segment cells, segmental organs and segments, of the origin and development of the alimentary canal and circulatory apparatus.

1886 Amer. Naturalist 20 181 With the increase in the volume and area of the cerebral cortex, which occurs mainly on the dorsal and lateral aspects of the anterior end of the neurula, the acceleration of growth of the brain substance also occurs on those aspects, and a downward flexure of the floor of the brain necessarily takes place.

1926 J. S. Huxley Ess. Pop. Sci. xviii. 259 The late gastrula or neurula is bisected as a whole.

1973 Nature 2 Mar. 55/2 In amphibian neurulae following initial removal of much of the totipotent blastula, abnormally few cells create a whole pattern.

1990 Sci. Amer. July 26/3 The signals induce part of the ectoderm to thicken into a structure called the neural plate. (At this stage the embryo is termed a neurula.)

1906 Proc. Royal Soc. B. 78 314 A ‘neurular’ stage is described, in which the medullary plate is present as a completely flattened and spatulate structure.

1999 Developmental Biol. 207 287 An anteroposterior organization in the neural crest at the neurular stage, destined for each pharyngeal region.