264 Dr. W. Nylander on neic British Lichens. 



to them elementarily, as may be seen in the pages of this 

 periodical, hesitate to come to such a conclusion." 



EXPLANATION OF PLATE XVII. figs. 1-9. 

 N.B. These figures are on the scale of l-12th to l-5400th of an inch. 



Fig. 1. Transparent cell, with rotatory protoplasm, charged with starch- 

 granules. Usual form : «, cell-wall, flexible ; b, rotating proto- 

 plasm, of which the current is indicated by the arrows ; c, nu- 

 cleus surrounded by starch-granules ; d, axial cavity. 



Fig. 2. The same, but a little larger. Cell-wall rigid. 



Fig. 3. The same, germinating (?) : a, cell-wall ; b, rotating protoplasm 

 charged with starch-granules, current indicated by the arrows ; 

 c, nucleus and starch-granules rotating in situ in the direction 

 indicated by the arrows ; d, axial cavity ; e, tubular extension, 

 which grew out to 1 -70th of an inch in one hour;/, starch- 

 granules, more magnified to show their characteristic shape. 



Fig. 4. The same, with tubular extension less advanced. 



Fig. 5. The same (but elliptical in form and larger) under the effect 

 of iodine, to show : — a, outer cell- wall ; b, inner cell- wall ; 

 c, starch-granules, rendered dark blue by the iodine ; d, nucleus. 



Fig. 6. The same, of a globular form, to show that state in which the 

 cell-wall was sufficiently plastic to admit of the protrusion of 

 short processes : a a, processes. 



Fig. 7. The same, in which five cysts of an endophyte had developed 

 themselves, and had enclosed nearly all the cell-contents. The 

 reniform starch-granules replaced by oil-globules, some of which 

 still remain outside the cysts, a a, cysts ; b, oil-globules. 



Fig. 8. The same, in which the cysts (three) of the endophyte had de- 

 veloped themselves, had pierced the cell-wall of their host, 

 according to their custom, and had discharged their progeny 

 into the water : a a, empty cysts ; b, remaining oil-globules. 



Fig. 9. The same, with three cysts of the endophyte, under iodine : 

 a a, cysts containing protoplasm (sarcode ?) and oil-globules, 

 all rendered brown by the iodine ; b, remainder of starch-gra- 

 nules and protoplasm outside the cysts rendered dark blue. 



XXXV.— Notulce Lichenohgicce. No. XXVII. 

 By the Kev. W. A. Leighton, B.A., F.L.S. 



Dr. Nylander makes the following additions to our British 

 Lichens in the ' Flora,' Aug. 30, 1868, and Nov. 8, 1868 :— 



1. Pyrenopsis homceopsis, Nyl. 



►Similis P. grumuliferce Nyl. in Flora 1867, p. 369, sed sporis 

 majoribus (longit. O011-0-018 millim., crassit. O007-0;010 

 millim.) et thallo intus (prgesertim sub apotheciis) pallidiore, 

 gonimiis majoribus (crassit. circiter 0*007 millim.). Thallus 

 fuscus, tenuis, subgranulosus ; apothecia in humido statu 

 latit. circiter # 2 millim. ; epithecium incolor ; paraphyses 

 graciles. Iodo gelatina hymenea vinose rubens vel vinose 

 fulvescens. 



