162 LICHENES. [Lepraria. 



in the centre. Ach. Syn. p. 116. — Thelotrema clausum, Schcer. 

 Lich. Helv. p. 68. n. 122. — Lichen clausus, Hoffm.—L. exanthe- 

 maticus, Sm. in Linn. Trans, v. 1. p. 81. t. 4. /. 1. E. Bot. 

 t. 1184. — L. volvatus, Fill. 



On exposed calcareous rocks. — Acharius observes that this curious 

 little plant recedes in character from its congeners ; and Mr. Borrer that 

 it has, in its nature, the closest affinity with Lecidea marmorea, Ach. 



4. T. Hutchinsicc, Borr. {Miss Hutchins Thelotrema); crust 

 very white, warts of the apothecia crowded obsolete of irregular 

 figure at length expanding with a broken flocculose inflexed 

 orifice, the nucleus (inner apothecium) forming a dark-grey 

 pruinose concave disk with a white lacerated margin. Borr. in 

 E. Bot. Suppl. t. 2652. 



On the ground, encrusting fragments of heath, moss, &c, near 

 Bantry, Ireland, Miss Hutchins. — " This resembles a good deal the variety 

 as it probably ought still to be accounted, of the Acharian Urceolaria 

 scruposa, which in the Synopsis is called Gyalecta bryophila. Yet in the 

 structure of the fructification, it appears to agree essentially with the 

 type of the Genus 'Thelotrema, (T. lepadinum,) particularly in the 

 presence, in an advanced stage, of a thin margin to the discoid nucleus, 

 separate from the spurious one, formed from the substance of the 



thaUus." 



(True Lichens.) 

 c. Apothecia ? naked sporules (gongyli or pulvinuli), 



l FAM. V. CoNIOCARPEiE. * 



9. Lepraria. Ach. (Lepra, Hall.) Lepraria. 



Thallus crustaceo-leprous, spreading, adnate, uniform. Apo- 

 thecia none. Sporules naked, forming the thallus, scattered, 



and conglomerated, free Named from As/r^, leprosy; from 



the scurfy appearance of the species. — This genus is assuredly 

 among the most simple of what are called True Lichtns by M. 

 Fee. Though the infant granules may sometimes form an im- 

 perfect apparent crust distinct from the sporules; yet, in general, 

 this plant consists of an uniform stratum, more or less thick, of 

 minute granules, which some have considered merely as the 

 thallus of a plant of which the fructifications are unknown, 

 others as a mass of sporules, gongyli or pulvinuli of some authors, 

 propagula of Messrs. Turner and Borrer. These last-mention- 

 ed Botanists have, fortunately for science, written their History 

 of this Genus and I gladly adopt their arrangement and char- 

 acters, only removing those species (L. ceruginosa and L. 

 chlorind) which have filaments mixed with the granules, to the 

 Fungi. Dubis and De Candolle remark on Lepraria, " Genus 

 vix hujus familia? et ex elementis heterogeneis (Lichenum crusta 

 sterili, Fungorum, Algarum prima evolutione) probabiliter con- 

 flatum." Hence the L. ceruginosa has been referred to the Al- 



