232 PROCEEDINGS OF THE ACADEMY OF 



This species is remarkable for its thick, spongy epidermis of a whitish 

 color, much as in R. bullosa, Link. ; but that is a much larger species, with 

 the lobes of the frond not so much crowded, and with the upper surface 

 rugulose. 



RicciA ARVENSis, Aust. MSS., 1863. 



R. fronde solida subciliata incrassata orbiculari subradiatim pluries divisa 

 subgregario-imbricata in diaraetro 4 — 8 lineari, supra papuloso-reticulata 

 obscure viridi vel demum secus margines purpurea, subtus nuda vel obsolete 

 squamosa valde obtuseque carinato-incrassata ob sporangia tumentia valde 

 nodosa; lobis obtusiusculis obsolete emarginatis lineari-ellipticis vel fere 

 linearibus dichotomis versus apicem incrassatera leuiter dilatatis, apice in 

 statu junior! subadscendentibus vix canaliculatis, in ietate horizontalibus 

 subcompresso-acuminatis evidentius lateque sulcatis, margine planis acutis 

 (in adspectu incrassatis obtusisque) ; ciliis albidis brevissimis omnino incon- 

 spicuis subobsoletisve ; fructibus primum versus apicem loborum infra ca- 

 nalem agregatis, sporis angularibus fusco-atris reticulato-muricatis — Ilep. 

 Bor. Amer. Exsic. ined., No. 141. 



Var /?, hirta. Statura majora, fronde subtus magis purpurea etsquamigerula 

 margine evidentius ciliata, supra omnino hirta. — llep. Bor. Amer. Exsic. ined., 

 No. 142.— i?. hirta, Aust. MSS. 1864. 



On damp ground in cultivated fields and (the var.) in rocky places about 

 Closter, New Jersey, common. 



The canal occupies about ^ of the upper surface of the frond, and has a 

 plane or slightly convex bottom with abrupt sides. That portion of the frond 

 between the canal and the acute margin is slightly convex above as if thick- 

 ened. The typical form appears to be near R. paradoxa, De Not., but that is 

 described as being a smaller species, and the spores are said to be light-red. 

 The var. differs from R. cilifera. Link., in the fronds being purple and more or 

 less scale-bearing underneath, and not membranaceous on the margin. The 

 sporangia are placed rather towards the apex of the lobes as in R. palmata, 

 Lindbg. ; which appears to be a larger species, with the lobes of the frond 

 concave-canaliculate above, &c., and seems to be intermediate between this 

 and the following species : 



RicciA Lescuriana, Aust. MSS., 1863. 



R. fronde solida subciliata orbiculata stellatim vel subcruciatim divisa 

 incrassata, supra punctato-reticulata glauco vel cineraceo-viridi epidermide 

 macula purpurea supra fructum notata, subtus nuda concolore vel demum 

 purpurascente; laciniis bilobis vel di-trichotomis obcoidatis lineari-cuneatisve 

 (2 — 5 lin. longis 1 — 2 lin. latis) leniter concavo-canaliculatis, apice emarginatis 

 brevi sulcatis, margine hirsuto-ciliatis incrassatis obtusis subadscendentibus 

 ad apicem subinvolutis ; ciliis creberrimis brevibus albidis obtusis in statu 

 juniori subobsoletis ; fructibus sparsis nOn seriatis subbasilaribus, sporis 

 fusco-atris angularibus reticulatis : gemmis? numerosis ellipticis aterrimis 

 in frondis facie superior! versus loborum apicem jjositis quam sporis triple 

 minoribus. — Hep. Bor. Amer. Exsic. ined., N. 143. 



Var. a, cruciata. Fronde cruciatim parce^ divisa, laciniis ciliisque brevis- 

 simis. 



Var. /?, trichotoma. Fronde magis divisa, laciniis ciliisque longioribus. 



The var at occurs almost exclusively on damp ground in cultivated fields ; 

 the var. /? on rocky soil, associated with the var. of the preceding species, 

 and with R. sorocarpa and R. lamellosa. 



R. palmata, lAndhg., a closely related species, is described as having the 

 frond palmately lobed and the divisions broadl}' sulcate, with the ciliae ar- 

 ranged in a single series. R. Bischoffii, Huben , has the margin of the frond 

 membranaceous, the lobes much expanded, and sj ores twice as large ! The 

 var. a has much the appearance of R. bifurca, Hoffm., as figured in Lindbg. 

 Monogr. d. Rico. T. XX, f. 1, but that has the margin of the frond naked. 



[Dec. 



