exumbrella Zool.
(ɛksʌmˈbrɛlə)
[mod.L., f. L. ex- out + umbrella 7 b.]
The aboral or outer surface of the umbrella of a jellyfish. Hence exumˈbrellar a., of or pertaining to the exumbrella.
| 1886 A. W. Greely Arctic Service II. 400 The genus Nauphanta is a characteristic one, and is remarkable in the peculiar sculpturing of the exumbrella, the division of the umbrella on the exumbral side into a central and coronal or peripheral zone. 1888 Rolleston & Jackson Forms Anim. Life 745 The mesoglaea of the aboral aspect of the bell is much thickened to form the umbrella s. exumbrella. Ibid. 783 If the Ephyra be regarded from the dorsal, i.e. exumbrellar aspect. Ibid. 784 The sense-bodies are usually protected by a dorsal, i.e. exumbrellar covering-piece or hood. 1897 Parker & Haswell Text-bk. Zool. I. 124 The convex outer surface of the bell or umbrella..by which the zooid was originally attached to the blastostyle is distinguished as the ex-umbrella, the concave inner surface as the sub-umbrella. 1907 Gentl. Mag. July 97/2 The tentacles..imbedded in ridges of jelly of the exumbrella. 1940 L. H. Hyman Invertebrates I. vii. 373 The medusa form resembles a deep to shallow bowl of gelatin, termed the bell or umbrella; the convex aboral surface is called the exumbrella, the concave oral surface, the subumbrella. 1967 P. A. Meglitsch Invertebrate Zool. vi. 151/1 Small particles and plankton are caught in slime secreted on the exumbrella. |