The Genus Phyllospadix 413 



taken from an anther three days open, and they may possibly 

 live a much longer time in the open sea. 



The stigmas are described as capillary by most authors ex- 

 cepting Ascherson. Thej^ are ovate lanceolate, acuminate, 

 thin, irregularly lobed and laciniate. 



The nucleus of the single, orthotropous, pendulous seed, 

 enclosed in a strong double testa, is carinate dorsallj^ some- 

 what compressed, and presents, like all the forms related to it, 

 a largely developed hypocotyl with no surrounding endos- 

 perm. The hypocotyl has two lateral fleshy lobes folded 

 toward the cotyledon (Fig. H). The narrovv- cotyledon, two 

 millimeters long, is tubular and two-lipped, the posterior lip 

 two-lobed and shorter. Enveloped by the cotyledon are two 

 to four alternately shorter flat laminae, obcordate or roundish, 

 the first leaves of the plumule (H, lower fig.). 



In various places we have referred to the bearing of peculiar 

 morphological features upon the generic characters of Phyl- 

 lospadix. We now turn to the anatomy of the vegetative 

 organs. 



The rhizoma has marked provisions for clinging to a hard 

 substratum, but in itself is brittle and weak. The leaves and 

 stems are correspondingly strong and flexible, the root firm 

 and resistant. 



The rhizoma is almost wholly a mass of parenchyma. Of 

 the three bundle-traces the middle one only shows a few poorly 

 developed annular, reticulated or dotted vessels, some weak 

 libriform cells, andnostrong wood fibres. Sclerenchyma fibres 

 are wholly wanting. Indeed, the only strengthening tissue in 

 the rhizoma is coUenchyma-like cells appearing in a few 

 rows in the cortex. 



Turning to the figures of the root-sections (R), it will be 

 seen that the firmness in the root is due to the broad sheath 

 of epidermal and hypodermal cells with remarkably thickened 

 walls, the parenchyma of the middle region remaining thin- 

 walled. 



Figure L shows a transection of the leaf of Ph. Torreyi 

 near the epidermis; and M, (lower fig.) transections of a por- 



