RIDDLE: THE LICHENS OF BERMUDA 155 
53. Collema bermudanum Tuck. in herb., sp. nov. 
Thallus foliaceus laxe adherentis irregulariter crebre laciniatus, 
siccus rigidus madefactus gelatinosus, lacinulis inciso-crenatis, 
ad I mm. latis, crassiusculis planis scrabiusculis apicibus turgidis 
adscendentibus imbricatis, in pulvinulos constipatis 5-10 mm 
diam., isidiis granulisque destitutus, superne atrovolivaceus 
subtus nigrescens; strato corticali destitutus. Gonidia nostocacea. 
Apothecia dispersa primum immersa demum subsuperficialia, ad 
0.6 mm. diam., disco badio plano, margine thallino crasso integro 
persistente. Sporae incolores oblongae 4-loculares, 20-30 X 
te ik. 
On calcareous rocks, Walsingham, collected by Professor W. 
G. Farlow, 1880. 
Type-specimen in the Cryptogamic Herbarium of Harvard 
University. 
In a letter to Professor Farlow, under date of August 25, 1881, 
Tuckerman wrote of this species: ‘‘Collema cum C. furvo forsan 
comparabile sed distincta.”’ 
54. COLLEMA FLACCIDUM Ach. 
Without definite station, Brown, Britton & peas 1348. 
55: COLLEMA NIGRESCENS (Huds.) Ach. 
On Avicennia, Walsingham, W. G. Farlow. 
56. Collema thamnodes Tuck. in herb., sp. nov. 
Thallus fruticulosus irregulariter ramosus in pulvinulos 
Constipatis 5-10 mm. diam., ramis erectis compressis, circa 3-5 
mm. altit., 1.2 mm. latit., 0.5 mm. crassis, partim crebris isidiis, 
Viridi-fuscus vel fusco-niger; strato corticali destitutus. Gonidia 
nostocacea. Apothecia ignota. 
On calcareous rocks, Walsingham, collected by Professor W. 
G. Farlow, 1880. 
Type-specimen in the Cryptogamic Herbarium of Harvard 
University. 
57- LEPTOGIUM MARGINELLUM (Sw.) Mont. 
On Jasminium, Paynter’s Vale, E. G. B. 368; on J uniperus, 
without definite station, Brown, Britton & Seaver, 1410, 1586 
(beautiful specimens!). 
