PHYSMA. 115 



On the earth, Ohio (Lea), Tuckerman in Lea. Catal. Cincin. 

 1848. New England. Illinois, Hall North Carolina, Curtis. 

 South Carolina and Florida, Eavenel. Alabama, Peters. Texas, 

 Wright. And, on calcareous pebbles, Kansas, Hall. 



In patches of the lichen from the Organ mountains, Texas 

 (Wright], the exterior fronds are differenced from the small, 

 round, interior ones, serving only as margins to the solitary apo- 

 thecia, by their greater size and length, and their lobation; 

 much as the radiant, exterior squamules of squamulose Panna- 

 rice, when compared with the small, interior ones. 



2. H. polyspora, Tuckerm. in litt. ; thallus much as in the 

 last, but besprinkled with the numerous, very small apothecia 

 (scarcely exceeding O mm - 5, in width) which are even with the 

 thallus, and blackening. Spores numerous in the thekes, rounded 

 and ovoid, from brown becoming decolorate, 2-5 mic. in the long- 

 est diameter. 



Mountains of Colorado, T. S. Brandegee; comm. by C. J. 

 Sprague. The thallus appears to be more continuously corticate 

 below than in n. 1. 



XXI. PHYSMA, Mass. 



Apothecia scutellseforrn. Spores ellipsoid, simple, with- 

 out colour. Thallus foliaceous ; clothed beneath with a dis- 

 tinct, finally spongy hypothallus. Gonimous layer consti- 

 tuted of gonimia, which are concatenate, and dispersed, 

 amid lax filaments, in a homogeneous pulp; as in Collema. 

 It is to the genus last-named that the first species 01 

 Physma was always referred ; as the other also, by Mon- 

 tague. And it cannot well be questioned that the two are 

 congenerical ; but P. luridum is far closer to Pannaria rubi- 

 ginosa and P.fulvescens than is P. byrsceum to any Colleme- 

 iue lichen. No more pregnant example can be cited, among 

 foliaceous species, of the intimate relationship of Pannariei 

 to Collemei ; or of the unnaturalness of attempting to place 

 these families in different Orders. 



1. P. byrsceum (Afzel.) ; thallus ample, orbicular, cartila- 

 gineous-coriaceous; minutely wrinkled; lead-coloured (cineras- 

 cent) ; the discrete, radiant, linear lobes dilated and crenate at 



