338 ON GYMNOMITRIUM OBTUSUM. 



•8x-25, -25X-25, -25x-24, -26x-23, -28x-21, -22x-21 

 diameter. 



Eootlets few, hyaline, arising from the under side of stem where 

 the two series of leaves join, ascending to about the middle of stem; 

 the leaves have to be carefully separated from stem before the 

 origin of the rootlets can be seen. 



Leaves ovate, roundish ovate, obovate, sometimes broader at 

 the lower half of leaf, some broader at the upper, concave, bidentate, 

 margin entire (not speaking of segments) except occasionally at the 

 outside of leaf opposite where the segments end, or a little lower, 

 is a shallow hollowing out; in one leaf this was so marked that 

 the basal margin appeared toothed ; upon being magnified V slight 

 irregularities may be noted by the marginal cells not running 

 regularly round the side of leaf, but where the leaf increases in 

 breadth rows of four, five, and six cells are as it were added to the 

 leaf; sinus shallow, extending to a depth of from one-fifth to 

 one-fourth of the leaf; at the base of sinus sharp, with the segments 

 frequently slightly overlapping, widening out broadly, with the 

 segments broad, obtuse, nearly of equal size ; each segment of leaf 

 very concave, forming at the top of each leaf two spoon-shaped 

 hollows ; segments finely, roundly crenulate on both the inner and 

 outer sides ; cells on each side of sinus from ten to fourteen in 

 number ; the leaves have a hyaline border of irregular depth which 

 is distinctly reticulated to the edge, sometimes the whole leaf 

 hyaline, others (young terminal leaves) green to the very margin ; 

 these terminal leaves are also often in the middle reddish brown 

 coloured, pale green at the base which gradually changes into 

 reddish brown and increases in intensity, then suddenly hyaline. 



Size of leaf, -9mm. x '7mm., -9 x -65, -9 x -6, -875 x -6, -85 x '7, 

 •825 x -6, -8x-7, -7X-85 (male), -775 x -6, -75x-65, -75 x -6, 

 •725 x -55, -7 x -5, -65 x -5, -6 x -525. 



Segments, -4 and -225, -325 and -3, -3 and -25, -175 and -15 broad. 



Segments about -25 deep. 



Structure.— Marginal cells quadrate small (parva) cells of the 

 centre between mediocres and parvula (see Spruce, 'Journal of 

 Botany/ "On Ammoclada," page 6, 1876); in the segments the 

 outer margin of same rounded, the second and third series of 

 marginal cells are also small, then they gradually increase in size 

 and assume a more hexagonal oblong shape, being large and six- 

 sided m the basal centre of leaf; in the other portions of leaf four-, 

 five-, and six-sided. Trigones small, but very distinct. 



Size: marginal cells, -002 x -002; centre of leaf, -005 x -0025, 

 •004 x -003, -004 x -002, -00375 x -002, -0035 x -0025, -003 x -002. 



Trigones rather less than -001. 



Male stems swollen at the ends where are the antheridia ; in a 

 few stems I have found a few antheridia in the middle of the stem ; 

 pengomal leaves but little altered from the others, more swollen at 

 the base, and rather broader. 



Antheridia few, oval, with swollen base when young; bearers 

 as long or longer than the antheridia (some twelve cells long) ; the 

 outer skin of antheridia very persistent. 



