BOTANY 



Mentha hirsuta {continued) 



b. subglabra (Baker) 



c. citrata (Ehr.) . 



— sativa, Linn. . . . 



b. paludosa (Sole) . 



c. subglabra, Baker 



— rubra, Sm 



— gracilis, Sm. 



b. cardiaca. Baker . 



— gentilis, Linn. 



Mentha gentilis (coniinueif) 



h. Wirtgeniana(F.Schultz) 

 c. Pauliana (F. Schultz) . 



— arvensis, Linn 



b. Nummularia (Schreb.) 



c. agrestis (Sole) 



d. prsecox (Sole) 



e. Allionii (Bor.) 



— Pulegium, Linn. . 



b. erecta, Syme 



NAIADACEiE 



The county is very rich in this Order, both the 'Broad' country 

 in the east and the ' Fen ' land in the west giving unusually favourable 

 habitats for it. The list has been most kindly corrected by Mr. Arthur 

 Bennett, w^ho is the acknowledged authority on the Order, and it con- 

 tains Naias marina, discovered by him in 1883, and only known in Great 

 Britain in the locality in which he found it. 



Naiadace^ 



Triglochin palustre, Linn. 



— maritimum, Linn. 

 Potamogeton natans, Linn. 



— polygonifolius. Pour. . 



— coloratus, Hornem. . 



— alpinus, Balb. . . . 



— heterophyllus, Schreb. 



— lucens, Linn. . 



b. acuminatus, Fr. 



— decipiens, Nolte . 



— angustifolius, PresL . 



— prxlongus, Wulf. . 



— perfoliatus, Linn. . 



— crispus, Linn. . . 



b. serratus (Huds.). 



— densus, Linn. . 



Potamogeton zosteraefolius,Schum, 



— acutifolius. Link 



b. major, Fieber . . . 



— obtusifolius, Mert & Koch . 



— Friesii, Rupr 



— pusillus, Linn 



b. tenuissimus, Koch . 



— trichoides, Cham 



— pectinatus, Linn 



— interruptus. Kit 



b. scoparius 



var. pseudo-marinus . 

 Ruppia spiralis, Hartm. . 



— rostellata, Koch . . . . 

 Zannichellia palustris, Linn. . 



— pedunculata, Reichb. . 

 Zostera marina, Linn. 



Naias marina, Linn 



FILICES 



EQUISETACE^, LYCOPODIACEiE, MARSILEACE^E 



Ferns which can only grow on rocks are of course absent from the 

 county, but their absence is made up for by the extraordinary abundance 

 and variety of those species which are found in marshes. Lastraa 

 cristata has certainly been found in all four divisions, though it is to 

 be feared that in one of them, the North-Central, it is almost, if not 

 quite, extinct. With it in some of its localities grows L. uligmosa and 

 also L. spinuhsa, but the last is common compared with the two former. 

 In some of the marshes along the Bure and in the Broad country L. 

 Thelypteris is as abundant as Pteris aquilina on the heath-land, and is mown 

 and used like it for packing and rough litter. Osmunda regalis has been 

 harried by collectors for sale until many of its clumps have disappeared ; 



57 



