Mr. R. Spruce on the Mmci and Hepaticce of the Pyrenees, 487 



Hah. Zi_2 per Pyrenseos sylvaticos, rupestris, frequens sed ra- 

 rissime fructificans ; juxta lacum Seculejo capsulis deoperculatis, 

 22 Sept. 1845, legi. 



307. Z. viridissimus, Smith, Fl. Brit. p. 1224 (sub Dicrano) ; 

 Br. Europ. /. c. p. 7. t. 1 ; M. P. 243. 



Hab. Zj ad arbores circa Pau et Bagneres, plerumque sterilis. 



308. Z. conoideus, Schwgr. Suppl. 2. p. 138. 1. 137; Br. Europ. 

 /. c. p. 8. t. 2. 



Hab. Zj P. c. in truncis populi vetustis juxta pagum Pouzac ! 

 (Philippe !). Estafforte, Hte. Garonne (Brondeau in hb. Dufour). 



In these specimens the leaves are often nerved throughout, and 

 the nerve even excurrent into a short mucro. The sporular sac rises 

 above the mouth of the capsule before it is divided into cilia, which 

 are two cellules in breadth near the base, sometimes sixteen in number, 

 the intercalary cilia being far shorter than the others, 



TribuS 25. PTYCHOMITRIEiE. 



60. Ptychomitriurnf Bryol. Europ. 



309. P. polyphyllum, Dicks. Crypt, fasc. 3. p. 7 (sub Bryo) ; 

 Br. Europ. Ptychom. p. 4. t. 1 ; M. P. 244. 



Hab, Zi_3 in saxis graniticis regiouum sylvaticarum : e vulga- 

 tissimis. 



310. P. incurvum, Muehl. Cat. Plant. Amer. Sept. p. 98 (sub 

 Grimmia). Weisia incurva, Schwgr. Suppl. 2. p. 51. t. 116. 

 Grimmia Muehlenbergii, Brid. Br. Univ. 1. p. 181. Ptychomi- 

 trium piLsillum, B. et S. ! Br. Europ. Ptychom, p. 5. t. 1; SuUi- 

 vant ! Musci Allegh. n. 135. 



Hab, Zj P. occ. in muro prope Oloron. Csespitem unicum in- 

 veni. 



Leaves composed of two layers of cellules except near the base ; 

 the margins often thickened ( = 2 cellules) ; the nerve =3-5 cellules ; 

 the obtuse apex cucullate. 



Tribus 26. Orthotrichace^, Bryol. Europ. (ex parte). 

 61. Orthotrichum, Hedwig. 

 Obs, This genus includes but few rupestral species, and only two 

 of these (0. anomalum and cupulatum) have their normal station on 

 calcareous rock. Of the species which inhabit the bark of trees, it 

 is remarkable that those with an exserted capsule (Ulota, Bridel) pre- 

 fer young oaks, while those with an immersed capsule prefer poplars, 



§ 1. (= Ulota, Bridel.) 



311. O. crispulum, Bruch. Mst. in Brid. Br. Univ. 1. p. 793 ; 

 Br. Europ. ! Orthotnchum, p. 23. t. 12 ; M. P. 245. 



Hab. Ziinf. ad arbores in sylvis Pyren. occidentaliuni, locis 

 Jurancpny Gan, &c. 



