14 DIPLOrAl'PUS LINARIIFOLTUS. SANDPAPER STAR-WORT. 



outer row of short, stiff bristles, the inner of capillary bristles as 

 .long as the disk florets; while in Astei' the pappus is single." 

 The fact is, this is one of those cases where general appearance 

 suggests differences which science can scarcely find. Very few 

 would take our present species for an Aster when first found. 

 Its general resemblance is with the genus known as DiplopappiLs, 

 but in this species the student will scarcely find the double pap- 

 pus, the outer row being nearly wanting. In preparing our Fig. 

 2, it was a point to show this, but it is so very small that without 

 a laroer diao^ram it cannot be seen. Our botanical te.xt-books 

 scarcely give a correct idea of the small size. Dr. Chapman 

 merely says of all the genus, "pappus of capillary bristles in two 

 rows, the outer row much shorter," with nothinq; as to the lencrth 

 in this species. Dr. Gray in the "Manual" says the "outer series 

 is of very short, stiff bristles," and "very short bristles " in the 

 •' School Botany," Professor Wood alone comes down to figures, 

 and he tells us that the exterior pappus is " half a line long," 

 which is one twenty-fourth of an inch. It is a slender character 

 to build a genus on, and which perhaps would not have been 

 thought of in this connection only for the very different habit and 

 appearance of the group from Aster in general, as already noted. 

 Dr. Gray, indeed, classes it as Aster linariifolius in " School 

 Botany," though he notes that this is "of the old botanists, but 

 is strictly Diplopappus linariifolius^ 



The name Diplopappus is from two Greek words — diploos, 

 double, and pappus, an old man ; the latter name in botany has 

 been given to the usually gray hair-like crown which surmounts 

 the seeds in so many compound flowers, and is especially like a 

 gray head in the well-known Dandelion. In our Fig, 2 we see 

 what is known as the " inner row " of the pappus, almost enclos- 

 ing the floret, as the little flower is called. 



As already noted by Dr. Gray, the plant was known as Aster 

 by the older botanists, and under this name it appears in Ra)'s 

 Catalogue about the end of the seventeenth century as the "nar- 

 row rosemarv-leaved aster of Marvland." that celebrated author 



