ON TORTULi BRBVIEOBTRI8. 171 



Capsule elliptical — T. Irewroatris. Hook, and Grey. Lid short, 

 conical ; synoicous. 

 T. rigida, Scholtz. Lid long subulate ; 

 dioicous. 

 Capsule cylindrical — T. ambigua, Br. & Bch. Capsule erect; 

 dioicous. 

 T, a/oides, Br. & Sell. Capsule inclined ; 

 dioicous. 



T. brcvirostris appears to prefer old moss-covered limestone 

 walls ; T. rtgida, nuidenpped walls in oolitic or magnesian limestone 

 districts; T. ambigua, rabble heaps in chalk pits; T. abides, clay 

 banks; for it is in these localities that the species are respectively 

 found to grow most luxuriantly. 



For the excellent drawing accompanying this notice 1 am in- 

 debted to Dr. R. Braithwaite, whose kind assistance on this and 

 former occasions 1 take this opportunity of gratefully acknow- 

 ledging. 



A full account by Mr. Mitten of the history of the group of 

 Tortulcc to which T. brevirosiris belongs will be found in the 

 " Journal of Botany " for this month. 



Explanation of Plate xxiii. 

 1. Plants, natural size. 2. Capsules X 20. 3. Operculum X 50. 4. Part of 

 annulus. 5. Vaginula and inflorescence. 6. Stem X 20. 7. Leaves X 20. 7x. 

 Transverse section of a leaf. 8. Filaments from surface. 9. Areolation of margin 

 at upper part. 10. Areolation of basal angle. 



LICHENOLOGICAL MEMORABILIA, No. 5. 

 By The Rev. W. A. Leighton, B.A. Camb., F.L.S., F.B.8. Ed. 



On Lecidea Dilleniana (Ach.), and Opegrapha grumulosa, Duf. 



Our venerable and venerated confrere, the Rev. M. J. Berkeley, 

 in one of his excellent papers in the " Linnean Transactions," xxi., 

 p. 149, remarks that "The illustrious Mycologist, Elias Fries, on 

 more than one occasion expresses the far greater pleasure that he 

 has experienced in ascertaining with complete certainty a single 

 synonyme of the earlier writers than in discovering new species — 

 a sentence which will meet a responsive echo in the approbation of 

 most true lovers of science. There is indeed a great satisfaction 

 in clearing up a point hitherto obscure." 



This excellent remark was forcibly recalled to my mind on ex- 

 amining some specimens of Opegrapha grumulosa, Duf., from the 

 walls of the old Nunnery in Alderney, which had been determined 

 by Dr. Nylander, and sent to me by Mr. Chas. Larbalestier, who 

 has been the fortunate and acute discoverer of so many novelties 

 in our Lichen-Flora, in the* Channel Islands and elsewhere. This 

 lichen is in general external character and aspect very similar to 



