Glossary 



NUCLEUS (pi. NU'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 (06; cordatus, heart-shaped), like an inverted heart. 



OBESE / (obesus, 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 SAPKO- 



PHYTE. 



OBLONG, 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 -f pyriform, pear-shaped), inversely pear-shaped. 

 OBSOLETE, indistinct, very imperfectly developed ; hardly perceptible. 

 OBTUSE/ blunt or rounded. 



OCHRA'CEOUS, O'dlEROUS, O'CHREOUS, O'CHROID, O'CHRY, O'CHROUS, O'CHERY (ochre, 



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



OCHRA'CEOUS- RUFOUS (ochraceo-rufus} . (Yellow ocher + 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. 



OLEAGINOUS (oZewm, oil), oily or oil-like. 

 OLIVACEOUS, OLIVE (olivaceus, olivinus), a greenish-brown color like that of olives 



(Sepia + light zinnober-green.) 



OLIVE-BUFF (olivaceo-luteus). (Yellow ocher + cobalt-blue + 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 4- 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^IOSE (osmosis, thrust, push, impel), the impulse or tendency of fluids to pass 



through membranes and mix or become diffused through each other. 

 OSMOSIS (Gr. impulsion, pushing), the diffusion of fluids through membranes; see 



osmose. 



OSMOTIC, of or pertaining to or characterized by osmose. 

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



through which the spores are discharged. 



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