Glossary 



NUCLEUS (pi. NL T/ CLEI) (nucleus, a little nut, kernel, stone of a fruit), the central, 

 highly differentiated mass of protoplasm in a spore or other cells of a fungus, con- 

 trolling cell division and reproduction, functionally the most important portion 

 of a cell, for in it the process of cell division begins ; sometimes improperly ap- 

 plied to the oil globules or guttulse and the vacuoles within some spores. 



OB-, in composition "inversely." 



OBCLA'VATE (as if obclavatus, <o6, from; clava, a club), inversely club-shaped. 

 OBCON'IC, OBCON'ICAL (ob; conus, a cone), inversely conical. 

 OBCOR'DATE (ob; cordatus, heart-shaped), like an inverted heart. 

 OBESE / (obesns, fat), stout, plump. 



OB'LIGATE-PARASITE, can only grow as a parasite ; see facultative parasite. 

 OB'LIGATE-SAPROPHYTE, can only grow as a saprophyte. See FACULTATIVE SAPRO- 

 PHYTE. 



OB'LONG, two or three times longer than broad, with nearly parallel sides. 

 OBO'VATE, inversely ovate, having the broad end upward or toward the apex. 

 OBPYR'IFORM (ob -\-pyriform, pear-shaped), inversely pear-shaped. 

 OBSOLETE, indistinct, very imperfectly developed ; hardly perceptible. 

 OBTUSE/ blunt or rounded. 



OCHRA'CEOUS, O'CHEROUS, (XCHREOUS, O'CHROID, O'CHRY, O'CHROUS, O'CHERY (ochre, 



ocher, + aceous), ocher-yellow ; brownish-yellow. 



OCHRA'CEOUS-RUFOUS (ochraceo-rufus) . (Yellow ocher -j- burnt sienna + light red.) 

 OCHRE YELLOW (ochraceo-flavus) . The color of the pigment called yellow ocher. 

 OCHROS'POR.E (Gr. pale yellow), a group of fungi having ocher or brown-colored 



spores. 



OLEAG'INOUS (oleum, oil), oily or oil-like. 

 OLIVA'CEOUS, OLIVE (olivaceus, olivinus*), a greenish-brown color like that of olives 



(Sepia + light zinnober-green.) 



OLIVE-BUFF (olivaceo-luteus ) . (Yellow ocher -f- cobalt-blue -f- white.) 

 OLIVE-GREEN (olivaceo-viridis), a peculiar color, produced by the mixture of yellow 



and gray, resulting in a tint somewhat between olive and dull yellowish-green. 

 OLIVE-YELLOW (olivaceo-flavus). (Light-cadmium + black + white.) 

 OPAQUE', OPAKE', mostly used in the sense of dull, not shining. 

 OPER'CULUM (operculum, a lid, cover, <operire, cover, shut, conceal), a lid-like cover. 

 ORANGE (aurantius) , a deep reddish-yellow like the rind of an orange. 

 ORANGE-RUFOUS (aurantio-rufus) . (Neutral-orange or cadmium-orange + light-red.) 

 ORANGE-YELLOW (aurantio-flavus) , a color intermediate between orange and yellow. 

 ORBIC/ULAR (orbicularis, <^orbiculus, a little disk), having the form of an orb; hav- 

 ing the shape of a flat body nearly circular in outline. 

 ORDER, the most important unit of classification above the genus. 

 ORGANIC, pertaining to either living or dead animal or vegetable organism. 

 OS X MOSE (osmosis, thrust, push, impel), the impulse or tendency of fluids to pass 



through membranes and mix or become diffused through each other. 

 OSMO X SIS (Gr. impulsion, pushing), the diffusion of fluids through membranes; see 



osmose. 



OSMOT'IC, of or pertaining to or characterized by osmose. 

 OS X TIOLE, OSTI X OLUM (ostiolum, a little door), mouth of the perithecium ; orifice 



through which the spores are discharged. 



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