298 Linnaean Society. 



Subfam. I. POLYPODIACE^, R. Br. 



Sporangia globose, or oval, transparent, unilocular, pedicellate, or rarely 

 sessile, opening transversely by the elastic property of a vertical, rarely 

 oblique, articulated ring. 

 Tribe I. Polypodies. Sori punctiform or elongated, destitute of a spe- 

 cial indusium. 

 Examples. — Polypodium, Sw. Grammitis, Sw. Hemionitis, L. 

 Tribe II. AcrostichiejE. Sori amorphous, destitute of a special indusium. 



Example. — Acrostichum, L. 

 Tribe III. Pteride.e. Sori punctiform, or elongated transversely. In- 

 dusium lateral, attached exteriorly. 

 Examples. — Pteris, L. Adiantum, L. 

 Tribe IV. AspLENiEiE. Sori elongated, oblique. Indusium lateral, linear. 



Examples. — Asplenium, L. Diplazium, Sw. 

 Tribe V. Aspidie.<e. Sori punctiform, intramarginal. Indusium orbicu- 

 lar and central, or reniform and lateral, and attached interiorly. 

 Examples. — Aspidium, Sw. Nephrodium, Mich. B. Br. 

 Tribe VI. Dicksonies. Sori marginal. Indusium lateral, attached in* 

 teriorly, its free margin conniving with the indusiform margin of the 

 frond, forming a calyciform bilabiate cyst. 

 Examples. — Lindsaea, Dry. Davallia, Sm. Dicksonia, L'Herit. Tricho- 

 manes, L. Hymenophyllum, Sm. 



Tribe VII. CYATHEiE. Sori punctiform, intramarginal. Indusium caly- 

 ciform, or wanting. Receptacle elevated. 

 Examples. — Cyathea, Sm. Hemitelia, R. Br. Alsophila, R. Br. 

 These tribes are again subdivided into minor groups, founded upon cha- 

 racters derived from the venation of the frond, the position of the sori, and 

 the form of the indusium. Notholczna and Ceratopteris are referred to 

 the first, Ceterach to the fourth, and Onoclea to the fifth tribes. 



Nov. 3. — Mr. Forster, V.P., in the Chair. 



Mr. William Taylor, F.L.S., exhibited a sample of the oil obtained 

 from the fruit of Madia sativa, grown at Aspall Stoneham, near 

 Ipswich. 



Read, " A Note on the Bokhara Clover." By William Taylor, 

 Esq., F.L.S. 



Mr. Taylor obtained from Mr. Loudon a small parcel of seeds of the 

 Bokhara Clover (Melilotus arborea), which was sown early in April, 

 1839. The plant proved to be biennial, and stood the winter well. 

 On the 28th of April following, a part of the crop was cut down, the 

 stems measuring 15 inches in height ; and on the 28th of May, from 

 the same piece of ground, a second crop was obtained, which had 

 reached the height of 16 inches; a third on the 28th of June, 17 

 inches; a fourth in July, 16 inches ; a fifth in August, 15 inches; 

 and a sixth in September, measuring 14 inches. According to Mr. 

 Taylor's calculation, the Bokhara Clover would yield from 20 to 30 

 tons of green herbage per acre, and from 2 to 3 tons of strong fibre, 

 which appears capable of being manufactured into cordage. 



The flowers are white and very fragrant, and the plant does not 

 appear to differ specifically from the Melilotus leucantha, although 

 regarded by DeCandolle as a distinct species. 



