I 10 Morten ♦*. Porsild. 



pctaliini llaiisskn. (tcnnifloriini Tii. I-'it. & I.ck.) seems to lie witliin (he 

 limits of variation ol" any patch and lims liardly to dcservo the namo. 

 On tlio othor liand th(» var. albifiorum N vtii. is licrfditary constant. 

 Tilis faet may especially l)o obsorvi'd at the horders ol" i-iver heds. where 

 a series of eolonies may he started from a siiiijle patch and ocenrini,' 

 alonir one hraiuli ol' the ri^■er, hiit not alonej tlie othevs. 



, lMS!. Chamaenerium ambiguum rii. Fn. ^^ L\n(;e 



(? Ch. (Vignslifoiiiini X Idtifi'H'i'in. 



Strange to say this presumed hybrid has onlx heen observed on 

 Disko, but in return rather often. In Lyngmarken at Godhavn it has been 

 lound at least five times, and at Sinigfik r)9''22' also rather often; but 

 it seems only to occur in few specimens. I liave not Ix'en so forlunate 

 as to lind it myself in spite of intense searehing in piaces where both 

 species were growing side by side. The specimens from vSinigfik were 

 collecled flowering, Aug. 11. 1907, and the collector (L. Geisleh) adds 

 the information that it was growing among Ch. laliiolium and Ch. an 

 gustijolium, and that the last was not yet flowering. Its ovaries are big 

 like those of latifolinm, but they shrink in drying, and the ovules shrivel 

 completely; thus it seems incapable of fruiting. 



XXIX. Halorrhagidaceae. 

 X 219. Myriophyllum spicatum L. var. capillaceum Lance. 

 In ponds and pools. 



(Jnly observed a few times. Sofiehavn al Tasiii,ssarssuaq 68°25' (Bl.); lliviie(| 

 at Molsleinst^orf,' (W. &. H.); in a lake at the head of S. Stroiiifjord (>()".5o' (Jens.); 

 foiuid ;i f.'w lim. -s al Ikerasak To 30' (S. II. Vh.). 



A decided sonlhcrn I ype in Greenland; only known from thf 

 mentioned piaces. 



Some of the specimens from Ikerasak collected by \'an hoffen 

 were flowering already on the .luly 22, and tlici'eforc I siipposo it may 

 be able to fructilicate. 



Hibernates under ice. 



XXX. Hippuridaceae. 

 A 220. Hippuris vulgaris L. 



Will hardly be wanting in any smallei- lake or pond whicli do not 

 dry up during the summer. It is the niosl comnion and widesi disfri- 

 buted aquatic plant of Greenland. 



