1954] 



PLANTS COLLECTED IN NY AS ALAND 



29 



no question that the two groups based on the calyx are valid, and that this pro- 

 vides an easily observed way of separating them. It is a matter of opinion whether 

 one should follow E. Meyer, Choisy, Bentham and Hooker, Wettstein, and Rolfe's 

 early view in treating these groups as sections, or accept Rolfe's later view, also 

 that of Phillips, that they are genera; especially because, beyond the calyx, there 

 is no difference in facies. However, the morphology of the calyx seems of such 

 taxonomic importance in this family that I prefer to maintain Selago and Walafrida 

 as distinct genera. 



In a solitary specimen of an obvious Walafrida — H. Wild 1375 (Govt. Herb. 

 15912) from S. Rhodesia — nearly all the calyces are normally 3-lobed, and a very 

 occasional one may show an abnormally bifid lateral lobe. Such a casual abnor- 

 mality cannot be held to invalidate the genus. 



Calyx 5-lobed (Selago L. sensu stricto). 



Inflorescence corymbose or shortly rounded-capitate (S. tbomsoni). 



Cauline leaves mostly (1.5-) 2-5 mm. wide, narrowly lanceolate to 



linear-lanceolate. la. S. tbomsoni var. caerulea, 



Cauline leaves mostly 1-1.5 mm. wide, broadly linear, median and upper 

 ones mostly rather short, 4-8 mm. long (often longer in Nyasaland; 

 forms from Tanganyika and Kenya with narrow leaves about 1 mm. 

 wide may be separated from var. whyteana by their short leaves). 



lb. S. tbomsoni var. tbomsoni, 

 Cauline leaves 0.25-1 mm. wide, filiform to narrowly linear, median and 

 upper ones mostly rather long, 8 mm. long or more. 



lc. 5". tbomsoni var. whyteana. 

 Inflorescence an elongate ± pyramidal panicle, dense, or lax and com- 

 posed of usually ± pedunculate heads or short spikes. 

 Leaves glabrous, linear; panicle normally dense; corolla-tube 1.5-3 mm. 

 long; calyx-teeth linear-oblong, usually densely ciliate (S. 

 thyrsoidea). 



Leaves of main stem mosdy 1-1.6 cm. long; stems without numerous 

 short, lateral leafy branches; largest corolla-lobe about 3 mm. 

 long. 2a. S. thyrsoidea var. thyrsoidea. 



Leaves of main stem mostly 1.2-2 cm. long; stems with numerous 

 short lateral leafy branches; largest corolla-lobe about 2 mm. 

 long. 2b. 5". thyrsoidea var. austrorhodesica. 



Leaves of main stem mostly 0.6-1.2 cm. long; stems subsimple or 

 with numerous short leafy branches; largest corolla-lobe 1-2 mm. 

 long. 2c. S. thyrsoidea var. nyikensis. 



Leaves pubescent or puberulous, narrowly lanceolate to oblong-linear, 

 sometimes linear; panicle normally lax; corolla-tube 3-4 mm. long; 

 calyx-teeth triangular-acute or acuminate, less densely ciliate (5". 

 welwitschii). 



Stems and leaves sparsely to ± densely clothed with minute decurved 



appressed hairs. 3a. S. welwitschii var. welwitschii. 



Stems and leaves ± densely clothed with longer patent flexuous or 



straight hairs. 3b. S. welwitschii var. holubii. 



Calyx (2-) 3-lobed (Walafrida E. Mey. sensu Rolfe). 



Inflorescence corymbose or rounded, aggregated near the ends of the stem 

 and main branches. 

 Leaves filiform to narrowly linear, 0.3-0.8 mm. wide (W. swynnertonii). 



Leaves densely scabrid-pu be scent. 4a. W. swynnertonii var. swynnertonii. 



Leaves glabrous or very sparsely pubescent. 4b. W. swynnertonii var. leiophylla. 

 Leaves broadly linear to oblanceolate, 1-5 mm. wide. 



Leaves usually without axillary fascicles of smaller leaves near the 

 inflorescence, sometimes with fascicles much smaller than the 

 cauline leaves which mostly exceed 2 cm. in length; fruits dis- 

 tinctly muriculate; corolla-tube 1.7-2 mm. long, longest corolla- 

 lobe 1.4-1.6 mm. long. 5. W. angolensis. 

 Leaves on main stems all or almost all with axillary fascicles of 

 leaves which are conspicuous and often not much smaller than 

 the cauline leaves themselves which are very rarely as long as 



