442 Mr James Hardy on the Discovery of Psamma Baltica. 



and withered. If one lays the two corollas near each other 

 on a polished flat surface, the dust dispersed by arenaria is 

 very considerable, while from the other scarcely a single 

 pollen-grain is shed out. Very great also is the difference in 

 the abundance of pollen-dust, when we open an anther of 

 each. Under the microscope, the pollen-dust of arenaria 

 yields great symmetrical sphserico-prismatic grains, compacted 

 together with a polished skin ; while in Baltica there are 

 small, irregular-shaped, often adherent grains, with a some- 

 what wrinkled surface, (ubi sup.) On the other hand in the 

 number of the same work for 1872 (p. 185), Carl Noldeke is 

 not quite disposed to accept this view. In the Islands of 

 East Friesland, C. epigejos is a scarce grass, while Ps. Baltica 

 is not rare on those islands, where the Calamagrostis fails. 

 On the Northumbrian coast C. epigejos is aiogether absent, 

 the nearest station being Doddington Moor ; which speaks 

 in favour of the separate individuality of Ps. Baltica ; 

 although we very well know from geological considerations, 

 that the missing plant may now lie beneath the ocean, whose 

 encroachments, even in modern times, are unintermitted 

 along the whole British coast. I may here mention, that 

 another species of Psamma, Ps. australis, formerly mistaken 

 for Ps. arenaria, has within a few years past, been discovered 

 on the shores of the Black Sea and in Corsica*. 



Dr Henry Trimmen's description of Ps. Baltica, in the 

 " Journal of Botany," December, 1872, made entirely from a 

 large number of Northumbrian specimens furnished by Mr 

 Richardson, is here re-produced : — 



"Rhizome creeping, with a few barren leafy branches; roots 

 numerous, long, fibrous, given off from the nodes. Flowering 

 stem, 4 ft. to 5 ft. high, erect, hollow, glabrous, with three or 

 four leaves ; uppermost knot a little below the middle of the 

 stem, reckoning in the panicle. Leaves, sheath, smooth, blade 

 1-2 ft or more long, strongly involute when dry, very gradually 

 drawn out into a long, sharp but weak point \ in. wide at 

 broadest part when unrolled, upper surface occupied by closely- 

 set projecting ribs, the alternate ones more prominent, slightly 

 rough, not hairy, under (outer) surface plane smooth ; ligule f 

 in. long when complete, lacerated. Panicle slightly topping the 

 uppermost leaf, 8-12 in. long, by about 1 in. broad at widest, 

 cylindrical, attenuated at both ends, lobed, composed of tufts of 

 branches of various lengths some again branched, and pressed to 

 " " The Bosphorus," by R. du Parquet, p. 15. 



