438 CALIFORNIA ACADEMY OF SCIENCES ' [Proc. 4th Ser. 



Pannaria Del. 



P. molybdaea (Pers.) Tuck. — Indefatigable Isl. : south- 

 east side, rare on trees at 625 ft. (No. 437). 



Parmelia Ach. 



P. carntschadalis Eschw. — James Isl. : James Bay, rare on 

 dead trunks of trees at about 2150 ft. (No. 438). 



P. latissima Fee — Albemarle Isl. : Iguana Cove, abundant 

 on rocks on the side of the cHff above the cove, (No. 439). 

 Charles Isl. : common on rocks and tree trunks at 1000 ft. 

 (Nos. 440-441). Duncan Isl.: on rocks and dead twigs at 

 1200 ft. (Nos. 442-443). James Isl. : James Bay, common on 

 the trunks of trees at about 2000 ft. (No. 444). 



P. perlata Krumph. — Albemarle Isl. : Iguana Cove, Snod- 

 grass and Heller. Charles Isl. : Andersson. 



P. sp. {P. physodi Fries., P. aMnis Andersson) — Charles 

 Isl. : Andersson. Not collected by any of the later expeditions. 



Pertusaria DC. 



P. albinea Tuck. — Galapagos Ids. : Hassler Expedition. 

 Has not been obtained from these islands since. 



P. leioplaca (Ach.) Schaer. forma bispora — Tower Isl.: 

 on the trunks and branches of Bur ser a graveolens (No. 353). 



Physcia (DC.) Th. Fr. 



P. leucomela (L.) Michx. — James Isl.: Darwin. Not 

 obtained by any subsequent expedition. 



P. picta (Sw.) Nyl. — Barrington Isl.: common on the 

 branches of bushes and trees, (No. 359). Charles Isl.: 

 common on the branches of trees at about 1100 ft. (No. 358). 

 Duncan Isl.: common on rocks at 900 ft. (No. 357). Sey- 

 mour Isl. : south side, very abundant, encrusting rocks. (No. 

 360). 



Placodium DC. 



P. murorum DC. — Seymour Isl. : south side, encrusting 

 rocks along with Physcia picta, (No. 360). 



