appeared. But the point that needs most correction is, where it is said that the capsule is alto- 

 gether destitute of a ring. It is so minute., however, as to have wholly escaped the notice not only 

 of the author of Exotic Flora, hut also of that of other and very acute botanists, who examined the 







specimens 



An annulus indeed does exist ; but so sma 



and 



so unlike that part in other Ferns, 



that we may well be pardoned for having overlooked it 



should we now probably have detected 



it, were we not led to suspect its presence by knowing that some other Ferns now in our pos- 

 session, most closely allied to this, are furnished in their capsules with a remarkably large, very 

 broad, and almost complete ring. The Ferns we allude to are the Ceratopteris thalictroides of 

 Brongniart (Ellebocarpus olwaceus of Kaulf.), from the East Indies ; — what we take for Cerato- 



not two, ncarly allied 



pteris Gaudichaudii of Brongn.^ said to be from St. Vincent 



and 



f 



plants, from New Holland. There could not be a question of all these belonging to the same 



upon examining with the 



high power of the microscope the capsules of our 



natural group ; and 



Parkeria, we find on one side, near the point of insertion, a small oblong transversely striated spot 

 or disk, which may indeed be compared with a very reduced annulus of Ceratopteris , but which can 

 on no account be assimilated to that of the Filices Gyratce of Mr. Brown. 



Since we have now ascertained an annulus to be present, or something analogous to it, we can no 

 longer allow the genus to be separated from the Filices : but it becomes a question, to which of the 

 Divisions it should belong. Brongniart (see £>ict. Classique, v. 3. p. 350.) and Bory de St. Vincent 

 have ranked the Ceratopteris with the G/eichenece; the former indeed, doubtfully, and he expressly 



points out a difference in the nature of the annulus ; broad and flat 



mcomplete * in Ceratopt 



narrow and projectmg and complete in the Gleichenece. Indeed the whole nature of the capsules 

 different in the two, though that difference is not easily expressed in words. They are 



lar 



sre m 



Ceratopteris and Parkeria, quite sessile, of so thin and membranous and pellucid a texture. that the 



seeds are visible through the coat 



and, even in Ceratopteris, the ring does not appear to have any 



elastic property, nor are these capsules arranged in sori, but scattered upon longitudinal veins beneath 



the involucre 



The 



ds (incorrectly 



large, and when seen under the high power of 



the Exotic Flora, but well defined by Mr. Brown) 



microscope exhibit a most beautifully striated 



appearance. Their integument is comparatively thick and tough, and, when broken, it is found to 

 contain a transparent oily substance, which floats upon the table of the microscope. In short, the 

 whole habit of the plant, its place of growth, the situation of the capsules, 



the 



structure and that 



of the seeds 



all point out a group or tribe which cannot well be associated with any hitherto esta 



blished. On this account we have formed a new one. 



The Parkeriace^ are exclusively tropical plants, inhabiting Asia, Africa and America 



and we 



are at present acquainted with but two genera, — Ceratopt 



distinct annulus ; and our Parkeria 

 P. Zjockharti-f-. 



distinguished by its very larg 



and 



Of the latter we possess two species, Parkeria pteridoides and 



M. Brongniart attributes a double covering to the capsule of Ceratopteris ; but such a structur 

 we have never found to exist in any of our specimens. 



t 



We are aware that Mr, Brown attributes to his Teleozoma (Brongniarfs Ceratopteris) a complete 

 d it to be so in any of our specimens. 



P. Lockharti; frondibus fertilibus pinnatis, pinnis pinnatifidis incisis, stipite sequali cylindraceo. 



Hab. In lacubus prope Arima, Insula Trinitatis. D. Lockhart. 



but we have 





