Dr, R. Parnell on a new Species of Poa, 123 



simple panicle of few spikelets ; and the other, var. externa, 

 tall and slender, from 8 to 12 inches in height, with a simple 

 panicle of few spikelets. 



This grass is closely allied to Poa nemoralis, but differs from 

 it in the ligule of the upper sheath being prominent ; upper 

 leaf scarcely as long as its sheath ; all the joints situated on 

 the lower third of the stem, and covered by the sheaths; stem 

 slightly roughish : whereas in P. nemoralis the ligule is very 

 short ; upper leaf as long, often longer than its sheath ; upper 

 joint situated not below the middle of the stem, and not covered 

 by the second sheath ; stem smooth. 



From Poa montana* it differs in the florets being webbed ; 

 upper joint situated on the lower third of the stem; lower floret 

 equal in length to the large glume of the calyx : whereas in 

 P. montana the florets are not in the slightest degree webbed; 

 upper joint situated about half-way up the stem; lower floret 

 shorter than the large glume ; panicle longer, more slender, 

 of fewer spikelets on longer foot-stalks ; leaves more taper- 

 pointed. 



From Poa polynodaf, Parn., it differs in the florets being 

 webbed ; joints not exceeding three in number, situated on 

 the lower third of the stem ; upper joint covered by the second 

 sheath : whereas in P. polynoda the florets are not webbed ; 

 joints six or seven in number; upper joint situated above the 

 middle of the stem, not covered by the second sheath. 



From Poa cassia it differs in the florets being webbed ; lower 

 floret equal in length to the large glume of the calyx : whereas 

 in P. ccesia the florets are not webbed, and the lower floret is 

 longer than the large glume of the calyx ; the spikelets are 

 larger, and the glumes of the calyx nearly equal. 



From Poa compressa it differs in the outer palea being five- 

 ribbed; spikelets of three florets; joints three, confined to the 

 lower third of the stem : whereas in P. compressa the outer 

 palea is three-ribbed ; spikelets of five to seven florets ; joints 

 usually five, the upper one situated about the middle of the 

 stem. 



From Poa pratensis it differs in the florets being but slightly 

 webbed ; stem very much compressed and slightly roughish to 

 the touch ; upper leaf a very little shorter than its sheath ; 

 spikelets of three florets ; whereas in P. pratensis the florets 

 are copiously webbed, suspending the calyx by their silky 

 hairs ; stem smooth and round (except in the var. planiculmis, 

 in which the stem is slightly compressed) ; upper leaf much 

 shorter than its sheath ; spikelets usually of five florets. 



* This species was found on Ben Lawers by Dr. Greville. 



t This species is described in Dr. Parnell's work on Scottish Grasses. 



