BLASTOSPHERE
Blas"to*sphere, n. Etym: [Gr. sprout + E. sphere.] (Biol.)

Defn: The hollow globe or sphere formed by the arrangement of the blastomeres on the periphery of an impregnated ovum.

Note: [See Illust. of Invagination.]

BLASTOSTYLE
Blas"to*style, n. Etym: [Gr. sprout, bud + a pillar.] (Zoöl.)

Defn: In certain hydroids, an imperfect zooid, whose special function is to produce medusoid buds. See Hydroidea, and Athecata.

BLAST PIPE
Blast" pipe`.

Defn: The exhaust pipe of a steam engine, or any pipe delivering steam or air, when so constructed as to cause a blast.

BLASTULA
Blas"tu*la, n. Etym: [NL., dim. of Gr. a sprout.] (Biol.)

Defn: That stage in the development of the ovum in which the outer cells of the morula become more defined and form the blastoderm.

BLASTULE
Blas"tule, n. (Biol.)