Fig. 1. Epidermis of husk of wheat, spiral vessels and silicious crystals—2. Section of cane, silicious cell walls, internal portion filled with granular bodies—3. Cuticular layer of the onion, showing crystals of calcium carbonate and oxalate—4. Cells of garden rhubarb, with crystalline bodies and raphides—4a. Another layer filled with starch grains—5. Section of pear, testa, sclerogenous and granular tissue—6. Stellate hairs, sinuous cells and silicious parenchyma of leaf of Deutzia scabra, under surface—7. Silicious cuticle layer of grass, Pharus cristatus.
[PLATE XV.—Page 482].
RHIZOPODA.—GROMIA.—FORAMINIFERA.
Fig. 1. Astrorhiza limicola—2. Lieberkühnia paludosa—3. Micro-gromia socialis undergoing fission—4. A colony of Hertwig’s Micro-gromia socialis—5. G. Lieberkühnia—6. Egg-shaped Gromia, G. oviformis, with pseudopodia extended, magnified 500 diameters. “Hertwig Ueber Micro-gromia, archiv. für Mickr. Anat. bdx.”
[PLATE XVI.—Page 510].
SPONGE SPICULES.
Fig. 1. A portion of sponge, Halichondria simulans, showing silicious spicula imbedded in the sarcode matrix—2. Spicula divested of its matrix by acid—3. Gemmule Spongilla fluviatallis enclosed in spicula—4. Birotulate spicula from same—5. Gemmule after being steeped in acid showing reticulated coating of birotulate spicula—6. Gemmules of Geodia—7. Gemmule in more advanced stage of growth—8. Skeleton of the acerate form covered by rows of spines—9. Showing rings of growth and horny covering, and bundles of spicula of the genus Verongia—10. Sphero-stellate spicula of Tethya—11. Tricuspidanchorate and sphero-stellate spicula—12. Acuate-bi-clavate and other forms of spicula from Geodia—13. Clavate spicula covered with short spines.
[PLATE XVII.—Page 518].
ZOOPHYTES, ASTEROIDS, NUDIBRANCHS, AND ECHINOIDS.
Fig. 1. a. Astrophyton scutatum—b. Doris pinnatifida, back and side view—c. Æquorea Forbesina—d. Medusæ bud—e. Thaumantias corynetes—f. Echinus in an early free stage—g. Echinus sphæra—h. Cydippe pyleus—i. Ascidiæ—k. Botryllus violaceus, on a Fucus—l. Corystes cassivelaunus—m. Eurynome aspera—n. Ophiocoma rosula—o. Pagurus Prideauxii—p. Ebalia Permantii.