▁stam ens ▁( st amin odes ): ▁two ▁later al ▁st amin odes ▁form ▁what ▁appear ▁to ▁be ▁small ▁u pr ight ▁pet als , ▁which ▁are ▁white ▁t ing ed ▁with ▁pur ple ▁and ▁ 1 . 5 – 1 . 7   cm ▁long ; ▁two ▁central ▁st amin odes ▁are ▁partially ▁f used ▁at ▁the ▁base ▁to ▁form ▁a ▁lip ▁or ▁lab ell um , ▁ 2 – 2 . 5   cm ▁long ▁by ▁about ▁ 3   cm ▁wide . ▁The ▁lab ell um , ▁which ▁is ▁usually ▁smaller ▁than ▁the ▁upper ▁pet al , ▁b ends ▁backwards ▁and ▁is ▁usually ▁split ▁into ▁two ▁lo bes ; ▁the ▁sides ▁are ▁w avy . ▁ ▁The ▁single ▁functional ▁st amen ▁has ▁a ▁white ▁an ther , ▁about ▁ 1 . 2   cm ▁long , ▁with ▁yellow ish - green ▁ 6 – 8   mm ▁long ▁sp urs ▁formed ▁from ▁the ▁connect ive ▁t issue ▁between ▁the ▁two ▁caps ules ▁of ▁the ▁an ther . ▁The ▁ov ary ▁is ▁c ly l inder - sh aped , ▁about ▁ 1   cm ▁long , ▁expand ing ▁to ▁a ▁ 2 . 5   cm ▁long ▁caps ule ▁when ▁seed ▁is ▁set . ▁ ▁Tax onomy ▁ ▁Ros co ea ▁h ume ana ▁was ▁first ▁described ▁scientific ally ▁by ▁Isaac ▁Bay ley ▁B alf our ▁and ▁William ▁Wright ▁Smith , ▁two ▁Scottish ▁botan ists , ▁in ▁ 1 9 1 6 . ▁The ▁specific ▁ep ith et ▁comm emor