156 MISSOURI BOTANICAL GARDEN. 
Sta. Maria (959, a, 959, 5). 
The very narrow-leaved form (as in Madeira), which has been 
called var. lanceolata, but is not separated by Micheli in DC. 
Monogr. Phanerog. $- 32. : 
NAIADACEAE. 
*POTAMOGETON PuUSILLUs, L. Watson 228, (2) 608; 
Drouet 198. — B. & H. 428. f. 965. — Rchb. 7. 
pl. 22. 
Flores (960). San Miguel (961). Sta. Maria 
(961, a). 
As none of my specimens are in fruit, it cannot be said positively 
that they do not represent the Canary Island P. denticulatus, Lk., 
which, though merged into this species in Index Kewensis, is kept 
apart by some students of the genus. 
P. PECTINATUS, L. Watson 228, (2) 608, (3) 396; Drouet 198; Seubert 
25; Seub. & Hochst. 9.— B. & H. 428. f. 966.— Rchb. 7. pl. 19. 
Terceira.— Not recently collected, and very likely the preceding. 
*P. tucens. L.? Watson 228, (3) 383; Drouet 198.— B. 
& H. 426. f. 958. — Rehb. 7. pl. 36. 
San Miguel (962, Lagoa das Furnas). 
Concerning this, Mr. Arthur Bennett, who was good enough to 
look over my specimens of this difficult genus, says that though 
he is not prepared to propose a new name for it, it is not typical P. 
tucens, but somewhat approaches P. fluitans in fruit characters. 
*P. LescHENAULTH, Cham. & Schl. Linnaea. 2: 223. pl. 6, 
Fi Bsr 
Sta. Maria (969, a, 969, b, 969, c). 
Placed under P. fluitans in Index Kewensis. 
*P. poLyGoniIFoLius, Pourr. Watson 229. P. hetero- 
phyllus, Watson (2) 608, (3) 392; Drouet 198. ?P. 
natans, Seubert 25; Drouet 197; Watson (2) 608.— 
Rehb. 7. pl. 44. 
Corvo (963). Flores (964, 965, 966). Fayal. Pico. 
Terceira (967). San Miguel (968, 969; Brown, 270). 
*P. naTans, L. ?Drouet 197; Seubert 25; Seub. & Hochst. 
9; Watson (2) 608, (3) 392, in part.— Rchb. 7. pl. 
50. 
Mr. Bennett writes me that this occurs in the Berne herbarium 
from the Azores, collected by Mr. Hunt, — hence presumably from 
San Miguel or possibly Sta. Maria. 
