1893.] MICROSCOPICAL .JOURNAL. 105 



Seeds of Mullein ( Verimsnmi tliapsiis L.). 



n\ K. II. \V.\RD, .M. D., 



TKOV, N. V. 



(From Note-book Q of the American Postal Microscopical Club. I 



'• Tlicsc seeds are ratlier prcttv " says one. Well, that is good. 

 But to persons tliouj^htfiil enoutjh to go bevond this quite obvious 

 reflection they suggest questions of inuch greater interest. Giv- 

 ing, as mounted, no views ot" internal structure, their study pre- 

 sents the problem of the fitness of the ripe seeds, as we see them 

 here, to secure the success of the plant in perpetuating and 

 spreading tiie species, and to account ff)r its tlecidedlv peculiar 

 habits. 



This common Mullein is one of the most inveterate, not to sav 

 triumphant, of weeds. It does not lurk about thickets or partly 

 inaccessible regions, but boldlv and rapidly spreads over pastures 

 and waste places whenever it has a chance. P'rom its great size 

 and conspicuous bearing, this worthless intruder is easily exter- 

 minated by the careful and thrifty farmer ; but it quickly over- 

 runs half-cultivated fields, and becomes an intolerable nuisance 

 and a conspicuous disgrace to negligent or slovenly cultivators, 

 often taking possession ot whole fields for a succession of years. 

 Though evidently a naturalized foreigner, from Europe, it pros- 

 pers in a style that shows it well adapted to the conditions here ; 

 and in fact it makes itself at home, like some other alien citizens, 

 with a boldness and arrogance somewhat in proportion as it is 

 undesirable and unwelcome. 



Many a plant prospers greatly, by reason of possessing some 

 one valuable adaptation : but in this case there is no ditficultv in 

 seeing reasons by tiie half-dozen, any one of which would give it 

 more than a fair chance in the competition for place. Its biennial 

 habit enables it to get a sufficient start at almost any time, place, 

 or season, and to be ready for a vast amount of flowering at the 

 first opportunity. Its hard, stout, erect stalk, and big. clumsy 

 leaves, protected by a nauseous if not poisonous juice within, and 

 by a thick and almost impenetrable coat of woolly hairs (well 

 known to microscopists) without, are nearh" proof against the 

 force of wind and storm, the tramping and browsing of cattle, 

 and even the attacks of insect pests. The large, showy spike of 

 gaudy flowers, highly specialized also in form as well as color, 

 places the herb, notwithstanding the farmer's contemptuous name 

 of weed, far up among the higher ranks of insect-fertilized plants. 



Lastly, here are the seeds : {a) produced in immense numbers ; 

 (6) of small size, wasting no unnecessary material, small enough 

 to sow themselves easily in the crevices of the neglected soil 

 where they thrive, and just large enough to sprout successfully 

 during the short time required to take root in such places ; (c) 

 with a horny external coat, furnishing a maximum of mechan- 

 ical protection from external injuries, and probably able to resist 



