646 Zahlbruckner : Flechten-Flora Sud-Californiens 



Ad saxa schistosa in Catalina Island (no. 692). Legit Blanche 



Trask. 



A corticola Platygrapha Calif or nica (Tuck.) differt hypothallo 

 evolutio et apotheciis aliis. 



Chiodecton ochroleucum sp. nov. 



Thallus tenuis, effusus, inaequalis vel subrugulosus, tartareus, 

 ochroleucus, KHO flavens, CaCl 2 erythrinosus, medulla alba, I 

 vinosa fulvescenti. Gonidia chroolepoidea, cellulis ellips.oideis vel 

 oblongis, concatenatis. Pocadostromata thallo immersa vel rarius 

 demum modica prominale, irregulariter oblonga, usque 1 mm. vel 

 parum ultra longa, niveo-pruinosa. Hymenia stellata, substellata, 

 elongata, vel plus minus flexuosa, apicibus obtusis, humectata 

 mollia et turgescentia, ochracea, margine disphana, intus pallida, I 

 vinosa-rubescentia. Hypothecium et epithecium pallidum (lutes- 

 cens). Paraphyses tenuies,filiformes, connexo-ramosae. Asciovah- 

 cuneati, 8-spori, 53-62 fx longi et 20-22 fi lati. Sporae ovales vel 

 ovali-oblongae, hyalinae, transversim 4— 5-septatae, cellulis cylm- 

 dricis, 14-18// longi et 8 fi latae, episporio tenui. Receptacula 

 pycnoconidiorum punctiformia, nigra, nitida, immersa, excepto 

 vertice ; sterigmatibus basi ramosis, cellulis superioribus subinflatis, 

 longioribus, subfasciculatis ; pycnoconidiis filiformibus, arcuatis, 

 11-18 // in diam. et 1.5-1.8/i latis. 



Species distincta, a Chiodectone Calif arnica Tuck, hymenio pal- 

 lido et sporis minoribus latissibusque distat. 



Ad corticem Rhoidis integrifoliae in Catalina Island. Legit 

 Blanche Trask, no. 694. 



Arthonia patellulata caesiocarpa var. nov. 



Thallus tenuis, albens, determinatus. Apothecia caesio-pru- 

 inosa, in margine tamen plerumque nuda et nigra. Hypothecium 

 pallidum. Epithecium coerulescenti-fuligineum. Sporae 15-17/* 

 longae et 5.5—6 ^ latae. 



In ramulis Malvastri Thurberi in montibus Santae Monicae 

 (no. 690 pr. p.). 



Arthothelium pruinascens sp. nov. 



Thallus epiphloeodes, tenuis, determinatus, subrugulosus, cine- 

 reus vel flavido-cinereus, opacus, KHO — , CaCl 2 - , hypothallo 

 indistincto. Apothecia innata, parva, rotundato-angulata vel fere 

 oblonga, 0.2-0.3 mm. lata, plana, nigra, et caesio-pruinosa, humec- 

 tata turgescentia et nigra. Hymenium pallida fulvescens, I ascis 



