290 ON SOME POINTS IN THE MORPHOLOGY OF HAX,OPHILA. 



3 erectos parallelos riigosos apice subtrimcato-obtusos stigmatibus 

 undulatis marginatos clivisa, antlierarum 6 cii'ca mediam columnam 

 seqnidistaiitium loculis apice contiguis basi snbdiscretis. 



It will be evident from the above diagnosis that the Chinese 

 plant falls into the section Siphisia of Duchartre, as was conjectured 

 by Bentham ; but it does not fit exactly mto either of his sub- 

 divisions. By its only once-bent perigone-tube it agrees rather 

 with the second one (Klotzsch's Xepenthesia'-^'), from which it differs 

 ui habit, and in the perigone-hmb being six- not three-toothed. In 

 the two latter particulars it concords with the thfrd subsection 

 (Klotzsch's Pentodon f ), which, however, has a twice-bent perigone- 

 tube ; but I do not think this latter character is of much value, for 

 a little further prolongation of the tubular form, instead of its 

 spreading out into a limb, would produce the difference, and in the 

 present plant one hp only is erect, the other having the edges 

 cohering, so as to form a sac, like that of Cypripedixkm. In the 

 length of the lower sterile portion of the column, and its blunt 

 flattened apex, it differs, I believe, from all other members of its 

 section, and shows an aiD^^roach to Asteruli/tes. Duchartre assigns 

 parallel anther-cells to all AristoIocJdcc, but here they are certainly 

 distmctly, though slightly, divaricate at the base, whilst the two 

 anthers adnate to each lobe of the column are no nearer to one 

 another than to those of the adjacent lobes. It is undoubtedly a 

 remarkable species, which I suppose should stand between 

 A. saccata, WaU, and A. Thicaitesii, Hook. It appears to indicate 

 that it might be better to unite the two subdivisions in which these 

 are placed by Duchartre, and perhaps also to reduce Aster olytes to 

 Siphisia. 



ON SOME POINTS IN THE MOKPHOLOGY OF 

 HALOFHILA. 



By I. B. Balfour, Sc.D., F.L.S. 



[Notes read at the Meeting of the British Association. August Idlh, 1878. |] 



Xaiadacea present many peculiarities in organization. I need 

 only refer to the terminal nature of the stamen in Xaias, as 

 described by Magnus, and to the character of the ovule in Zostera, 

 I\}ij>pia, &c., in support of the statement. In the morphology of 

 Halupjiila, which I have recently been studying, there are several 

 pomts of great interest, but I shall only here refer to two. 



This genus includes a few marine plants, growing in widely 

 spreading patches on sandy flats in the troi)ics, at the limits of 

 ebb-tide. On looking at such a form sls H. oralis — the type of 



* Klotzsch, ' Die Aristolochiacece d. Berliner lifcrbariuins,' t. ii., f, 11. 

 Duchartre, • Ann. sc. nat.,' 4e, ser., ii., t. 5, f. 0. 



+ Klotzscli, op. cit., t. ii., f. Vi. 



X A paper, with illustralious, on the genus Halophila, will appear in the 

 forthcoming part of the Transactions of the Botanical Society of Edinburgh. 



