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X. Contributions to the Lichenograpliia of New Zealand ; being an account, loith figures, of 

 some neio s/jme* 0/ Graphidece and allied Lichens. By Chas. Knight, Esq., F.L.S., 

 Auditor- General of New Zealand; and W. Mitten, Esq., A.L.S. 



Read April 19th, 18ti0. 



1 HE following enumeration of the species of Graphideas, additional to the Plora of New 

 Zealand, includes some very curious tropical forms, as well as a proposed new genus for 

 the reception of two nearly allied Lichens which do not appear to correspond with any of 

 the numerous genera with which this group seems overburdened. Great difficulty, how- 

 ever, attends the investigation of these obscm'e plants ; and much more seems yet required 

 to be known of the tropical forms, before the genera, as at present constituted, can be 

 considered as more than arbitrary divisions. 



Opegeapha, Ach. 



0. vARiA, Pers. 



Hab. On trees, Auckland. 



The following forms have been observed : — 



1. Thallus olive-brown ; apothecia superficial, slender ; rima a mere chink ; spores 5-9-sep- 



tate, measuring from O'OOOS to O'OOllS of an inch. 

 Pl. XI. fig. 15. a. sections of the apothecium ; b. thecte ; c. spores. 



2. ThaUus olive-brown tending to grey ; apothecia more or less immersed when moist, 



the margin separating in the middle ; spores 4-5-septate, measuring from 0'00024! to 

 0-0009 of an inch. 

 Pl. XI. fig. 16. a. section of thallus and apothecium; b. theca; c. spores. 



3. ThaUus dusky-grey ; apothecia immersed when moistened, oblong, open ; spores 3-4i- 



septate, measuring from 0*00025 to 0'0007 of an inch. 

 Pl. XI. fig. 17. a, section of thallus and apothecium; b. spores. 



The form 2 closely resembles the O. varia var. trklens, Schser. Lich. Helv. Exsic. No. 98. 

 In all essential particulars the New Zealand forms agree with the European. 



0. CINEE.EA, Knight & Mitten. Thallus ashy-grey, pulverulent, sometimes obsolete ; apo- 

 thecia superficial, simple, oblong, straight or curved, closed ; spores bro^vn, 3-septate, 

 sometimes 1-septate, and then contracted in the middle, frequently mural, measuring 

 from 0-00025 to 0-00075 of an inch. 



Hab. On trees, Auckland. 



The short thick closed apothecia readily distinguish this species from the preceding. 



Pl. XI. fig. 18. a. sections of apothecia; b. thecal; c. spores, in which the diflerent degrees ot septation 

 are seen. 



