&ARSILEACEJE. 



is three lobed, at the apex, and contains below this a cavity lined by 

 a yellowish membrane, filled with granular and viscid matter and 

 oily globules. 



S. cucullata, foliis subreniformibus in cucullum condupli- 

 catis, pilis solitariis e superficie ipsa exorientibus. 



S. cucullata. Roxb, Crypt. PL Cat. jour, Nat. Hist. IV. 

 p. 470. 



Hab. — Stagnant waters. Bengal. Tenasserim Coast. 



Descr. — Much branched. Under-surface covered with trown 

 hairs, longer and with a less suddenly attenuated terminal cell. 

 Joints of the stem short, so that the leaves are all close together. 

 Koots springing directly from the stem, about 15. leaves on short 

 stalks, subreniform in outline, so folded together that the margins 

 of the base are in contact. Hairs of the surface solitary, springing 

 immediately from the surface ; terminal cells with the same curious 

 withered appearance. Fructification not observed. 



Obs. — This species I take to be comparatively less de- 

 veloped than the preceding, founding my supposition chiefly 

 on the fact, that the leaves partly represent the immature 

 state of the same organs of S. verticillata. 



Sub-FAMILLAI. — AzOLLINvE. 



Radices solitarise, basi vaginatse, apice calyptrata?.* Folia 

 imbricantia, inferum immersum membranaceum. Organa 

 mascula ; filamenta moniliformia in partibus novellis caulis 

 et ramorum. Ovula per paria cauli affixa, in involucro e folii 



* The calyptra of the roots of Azolla has probably been considered to 

 be the torn-up end of the sheath surrounding the base of each root, 

 which can scarcely have escaped observation. But it is quite a distinct 

 organ ; the sheath at the base is perforated at its apex by the young root, 

 while the calyptra appears to be a seperation of its cutis, due to the de- 

 velopment of a radicle from each cell of the subjacent tissue. 



In this respect it has another curious analogy with Lemna, of the 

 sheath and calyptra of which I was aware in 1836, long before I saw 

 M. Schleiden's paper on Lemnaceoe. 



