Peyssomelia. SQUAMARIE.E. 501 



ct ab Ajardliio sterilia descripla, primus rite illustravit. Ipsc in 

 t rib us specicbus utrnnique frucfum observa\i. 



Ouod circumscripUonem generis altinel, pa rum liodio disscn- 

 liunt. Decaisne primuni (PI. de I'Ar. p. 168) Padinam rosoam Lamotir. 

 hue retulit; dein (Class, p. Ill) hanc bene ad Melobosias rcvocavil. 

 Novas species descripserunt Crouau, Montague ot Kiit/in^. 



I. Frondibus lota inferiors pagftut tircfissimc adnalis ; cysto- 

 curpionim nuclco oblonyo. siniplici. yemmidits 2 6 



constitute. 



{. P. HARVEYANA (Crouan. mscr.~) frondo Crustacea arclissime adnata, 

 cellulis radiantibus sti|er(iciei cylindraceis elonjatis, parane- 

 nialum articulis diametro duplo loii)]ioiibtis, sphrcrosporis obo- 

 vatis, cystocarpiorum nucleo oblongo simplici, fjemmidia ro- 

 tundata 2 i fovente. 



Peyssonnelia Harvcyi Crouan. mscr.! (partim?). 

 llab. in saxis calcareis oceani atlantici; ad littus Gall ire propo 



Brest (Crouan!). 



Frons pollicaris, calcc carbonica levilcr incrustata, tola inforiorc su- 

 perlicie arctissime adnata. Fila verticalia, quas frondem sterilem efficiunt, 

 articulis constant diametro scsqui-duplo longiorilius, a sectione vorticali 

 observatis rectangularibus, seclioiie horizontal! 5 G-cdris-, periphoriaiu 

 versus in fila excurrunt elontiota, collulis rcgulariter seriatis rectangula- 

 ribus (ut apparent) constitute. Vi-rructu 1'ructus oblong;e, nullo urdine 

 supra frondem sparsoe. Parancmata et spliaerosporarum et cystocarpiorum 

 simplicia, articulis diametro duplo-lriplo longioribus constantia. SphaBro- 

 sporas obovatas crassas cruciatim divisas vidi, paranematibus fere duplo 

 brcviores. Cystocarpia gcmmidiis mine 3 vel 4, s;rpissime duobus con- 

 stituta, oblongo, pedicello brevi liyalino al'lixa. (Jemmidia intra membranam 

 hyalinam laxius ambientem articuli singulo; in lilo Iransmutato, (juo con- 

 stituitur cystocarpium, plura ct unum supra alterum seriala, nunc 3 4 

 jira'sentilius lateraliter alterne plus minus promincnlia; matura licet intra 

 membranam cuhibita, rotundata. 



Peyssonneliani Dubyi Harv. (nee C.rouan) ad bane spcciem referunt 

 Cel:i Crouan. Milii planta Harveyi cum jirimaria Crouanii idcnlica vi- 

 detur. Nee specimina omnia a Crouan sub nomine dato mi>sa ad eandein 

 plantain pertincre puto. l'ro[)rio itaque Marte et paul.itim miitato nomine 

 cbaracteres specie! cxhibui. 



2. P. DUBYI (Crouan in. Ann. So. Nat. I84i p. 3GS) frondo cru- 

 stacea arctissime adnala, cellulis radiantibus siiperliciei pono 



