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Genus 12. LAMPRODERMA 



The genus is recognized instantly by the shining, silvery, 

 brassy, blue, or purple, more or less persistent peridium, which 

 is often brilliantly iridescent. Most of the sporangia have black 

 stalks and columellae. Several species may be found locally, 

 but not often, except L. arcyrionema which is common in large 

 developments on wood. The sporangia are globose with steel- 

 gray peridia which break away in large patches exposing almost 

 black, globose masses of capillitia and spores. The stalk is 

 black, slender, two or three times the size of the sporangium 

 and continues as a columella which divides into a much 

 branched dark capillitium. 



Genus 13. CRIBRARIA 



The genus, comprising about 20 species, is related to only 

 two other monotypic genera, Dictydium and Lindbladia, the 

 last not described in this paper. The developments are always in 

 sporangia on more or less crooked, dark stalks. There is no uni- 

 formly closed peridium, except occasionally in one species; and 

 there is no capillitium. The sporangium-wall, at the base forms 

 a cup or calyculus, which is often only a thickened base, or may 

 be absent entirely. Above, and merging into the cup, is a net of 

 slender threads more or less expanded or thickened at the 

 nodes. The spores lie within this net and are dispersed through 

 the meshes. The colors of the various species are yellowish, 

 brownish, purple-red or violet-blue. Species known to occur in 

 this region are rarely collected except C. intricata and C. tenella, 

 but these are typical of the genus and abundant. Both form 

 globose, ochraceous sporangia on dark stalks, with cups that 

 may reach to one-third the sporangial height, or smaller to 

 obsolete entirely. The nodes of the net in C. intricata are thick- 

 ened, dark, prominent, and polygonal or branching. In C. 

 tenella they are also thickened and dark, but rounded or glo- 

 bose, and not so prominent as in C. intricata. There are frequent 

 intermediates which cannot be placed definitely. Forms of C. 

 intricata with obsolete cups are also known as C. dictydioides 

 but such are only phases of C. intricata. The same phases occur 

 in C. tenella and are not taken seriously there. 



