Bicknell : Ferns and flowering plants of Nantucket 61 



Long Pond was two thirds of a mile from the north shore and 

 over three and a half miles from Miacomet Pond. Midway 

 between these waters is Hummock Pond, which extends nearly 

 three quarters of the distance across the width of the island. Here 

 the plant was not detected although it is reasonable to suppose 

 that it occurs throughout all three of these ponds. 



In the latitude of Nantucket Naias guadalapensis appears to 

 be unknown east of Nebraska although in the south it extends to 

 west Florida. Its general range is understood to be from Oregon 

 and Nebraska to Florida, Texas, and tropical America. 



If not native to Nantucket, it has evidently long been established 

 there and its occurrence at so great a distance from the nearest 

 point of its known range finds no ready explanation. If the plant 

 is susceptible of dissemination by birds, a wider dispersal in the 

 east might be expected. It is also against the probability of its 

 introduction by such agency that at its fruiting season the general 

 course of bird migration is not from the direction of those regions 

 whence the seeds might be brought. It may not be unduly 

 ianciful to suggest the possibility of its chance introduction 

 through the destruction of some vessel from tropic waters among 



tne many shipwrecks which have had their scene on Nantucket 

 shores. 



The following description is from the specimens collected : 

 Early becoming dull or brownish-green; stems 10-30 cm. long, 

 capillary, often procumbent below and rooting at the nodes, the 

 foots elongated and threadlike ; very fragile, widely alternate- 

 branched from the base and decompound, the ultimate divisions 

 3~7 cm. long ; internodes of main stem 4 cm. or less in length, of 



^ branches 5-20 cm.; leaves opposite, not at all or but little 

 ^curved, pellucid, 5-15 mm. long, O.75-1.5 mm. wide, linear, not 

 a a ll or only obscurely narrowed towards, the obtuse or abruptly 

 ? Cute a Pex, minutely sharp-serrulate with numerous teeth ; fruit 

 ^rovvnish, 2 -5 mm. long to the beaked style, about 1 mm. thick, 



' n ear-fusiform, sometimes slightly curved ; style 0.5 mm. long, 



wH^^ b'fld ; pericarp obtuse at each end and strongly marked 



anl i ab ° Ut twent .y longitudinal lines of transversely oblong rect- 



gular reticulations ; seed about 2 mm. long, under a strong 



gnt somewhat glittering from the varied reflections of the reticula- 



■"s, linear, slightly narrowed to either end, the ventral side 

 t a 'gnt, the dorsal slightly curved ; obscurely keeled on the ven- 

 tral ■* towards the base 



