Hel-i-co-nid´æ [N., < heliconius, of Helicon; idæ.] A family of butterflies.
Hes-per-or´nis [Gr. hesperos, western; ornis, bird.] Cretaceous carinate birds with rudimentary wings, short tail, and pointed teeth implanted in grooves.
Hip-po-pot´a-mus [Gr. hippos, horse; potamos, river.]
Hol-o-ceph´a-li [Gr. holos, whole; kepale, head.] A subdivision of Elasmobranchii in which the suspensorium of the lower jaw is continuous with the cranium, as chimæroids, etc.
Hol-o-thu-roi´de-a [Gr. holos, whole; thouros, rushing.] Worm-like echinoderms, with skin-like integuments, and circum-oral tentacles; including sea-cucumbers, sea-slugs, etc.
Ho-min´i-dæ [Lat. homo, man; idæ.] A family of primates restricted to mankind.
Hy´a-lo-plasm [Gr. hyalos, glass; plasma, < plasso, form.]
Hy´dra [Gr. hydra, Lernæan serpent, < hudor, water.] A fresh-water polyp, having the form of a cylindrical tube, surrounded at the mouth with a circle of thread-like tentacles, by which it captures its prey.
Hy´droid [Gr. hudor, water; eidos, form.] Resembling the hydra; pertaining to the Hydroidea.
Hy-dro-zo´a [Hydro-; zoon, animal.] Cœlenterates including Hydroids and jelly-fishes.