NATURAL SCIENCES OF PHILADELPHIA. 233 



RicciA SuLLivANTii, Austin MSS., 1863. 



R. terrestris, velutina, valde cavernosa, fulgida, luteo-viridis ; fronde 

 orbiculari celluloso-siicculenta radiatim pluries divisa diametro subsemipoli- 

 cari ; laciniis di-trichotomis linearibus (vel in statu junior! subcuneatis) 

 subinibricatis canaliculatis, apice tenuiori angustiori emarginatis, subtus 

 carinato-incrassatis concoloribus nudis (vel ut in E. Jlitilcmte oh epidermide 

 evanida ad apicem minute squamigerulis), margine undique tenuibus sub- 

 hyalinis crispato-undulatis cum serie celluhirum singularum hyalinarum 

 circumdatis crenulatisque iu statu siccati omnino adscendentibus ad apicem- 

 que suberectis, carina cavernoso-striata copiose radiculosa ob sporangia subtus 

 tumenti ; fructibus copiosissimis e frondis pagina superior! prorunipenti- 

 bus ; sporangiis supra non prominentibus in carina immersis singulatim natis 

 Stylo longo nigro coronatis, sporis obscure angularibus reticulatis sub- 

 inuricatis luteo-fuscis vel nigris. — Jlep. Bor. Amer. Exsic. hied., No. 147. — R. 

 cryslallina, Sulliv. Mosses of the U. S. p. 84. pro parte. 



On damp or wet ground, in fields and meadows, about Closter, New Jersey; 

 also Pennsylvania, Lesquereux. 



E. Sullivayiiii resemhif'S both small forms of R crystallina and terrestrial 

 forms of R. Jiuitans, Linn., but the former is distinguished by its less divided 

 frond with the divisions plane above and expanded towards the apex ; and 

 the latter by its divaricate lobes somewhat thickened at the apex, by its fewer 

 and smaller air-cavities, and by its sporangia rupturing underneath the frond, 

 as well as by its shorter style and smoother spores. 



[There are occasionally found, imbedded in largish cavities on the under 

 side of the frond, a bundle of rootlets, matted or coiled together. These 

 rootlets are apparently longer than those which fix the plants to the earth, 

 and have the interior surface papillose (a character common to the rootlets of 

 all Riccife). Their free end is much expanded and open at the extremity, 

 and towards this extremity they are filled with cubical green bodies, arranged 

 (mostly) in fours, and resembling the spores of a Conferva. What these bodies 

 are is doubtful ; it is barely possible that they are a sort of reproductive organ 

 belonging to the plant in whose tube-like rootlets they occur.] 



RiCCIA TENUIS, AuSt. 



R. fronde tenuissima valde cavernosa fibroso-nervosa saturate vel olivaceo- 

 viridi fulgida parce divisa, subtus parcissime squamosa concolore, squamis 

 albidis teniiissimis ligulatis ; laciniis rotundo-obovatis (2 — 4 lin. long. \h — 3 

 lin. lat.) planis, margine sinuato-undulatis, subtus ob costam tenuem anguste 

 carinatis, ad solum radicibus parcissimis tenuissimis aflfingentibus ; fructibus 

 in nervo sitis, sporangiis parvis depresso-globosis plerumque 2 — 4 aggregatis 

 in frondis pagina iuferiori protuberantibus sed e neutra prorumpeutibus, 

 calyptra tenuissima laxissime texta frondis substantiam arete adhserenti 

 stylo brevissimo apice praemorso (non dilatato) coronata, sporis parvis 

 globosis vel subovalibus fuscis valde echiuaceo-muricatis. — Hep. Bor. Amer. 

 Exsic. ined., No. 150. 



On wet, broken ground in open woods, near Closter, New Jersey; also near 

 Lawrence, N. J., James. 



The closely allied R membranacea, L. & G., differs in the SMfi-cavernous 

 frond with the lobes suddenly widened and subsulcate towards the apex, in 

 the oblong-rotund sporangia, and longer style dilated at the apex. R. nigrescens, 

 Mont., is doubtless also very near our plant, but the margins of the frond are 

 said to be ascending, — furthermore, the description is altogether too meagre. 



RicciA NATANS, Linn. 



The spores of this species vegetate upon mud in summer, and by autumn 

 the young plants become considerably developed : (vide Aust. Hep. Exsic. ined. 

 N. 144, B. ; also Lindbg. Monogr. d. Rico. t. 26, f. 1, under the name of R. 



1869.] 



