LEPTODON. 377 



slightly exserted, oblong, narrowed at the mouth. Lid conical, 

 acuminate ; peristome small, pale. Calyptra and vaginula 

 covered with long hairs. Dioicous. 



Hab. Trees and rocks in the south of England. Fr, rare, spring. 



A southern species, which fruits abundantly in the countries about the 

 Mediterranean, but is rather rare with us and usually barren. When dry the closely 

 rolled up branches have a very peculiar appearance, unlike that of any other of our 

 mosses ; the wide, obtuse leaves with a single nerve are also very characteristic. 



97. PTEFJGYNANDRUM Hedw. 



Primary stem creeping, stoloniform, secondary ascending 

 •with irregular, curved branches turned towards one side, often 

 flagelliform. Leaves imbricated, ovate or obovate, strongly 

 papillose at back ; nerve single, short. Cells linear-rhomboid, 

 shorter at apex. Capsule erect, symmetrical, sub-cylindric ; 

 peristome small, outer teeth short ; inner peristome of 16 short 

 irregular processes, without basal membrane or cilia. 



1. Pterigynandrum filiforme Hedw. (Hypnum filiforme 

 Timm.) (Tab. L. K.). 



In larger or smaller patches, sometimes almost entirely 

 prostrate, at others more erect and 1-2 inches high ; bright green 

 or brownish ; branches numerous, curved, usually pointing the 

 same way, very slender, often flagelliform, or short and obtuse. 

 Leaves of secondary stems and branches sub-similar, very small, 

 obovate or ovate-oblong, shortly pointed, not excavate at base, 

 closely imbricated or secund, when dry secund or closely 

 appressed, rendering the branches terete ; concave, shortly 

 acuminate or simply acute or rather obtuse ; margin reflexed 

 below, minutely denticulate at summit ; nerve usually faint, 

 reaching slightly above the middle or shorter and forked; cells 

 sharply and strongly papillose at back, the greater part shortly 

 linear-vermicular , at the tip wider and shorter, at mid-base 

 longer and more pellucid, at angles short, irregularly quadrate 

 and rectangular, in a few short rows. Seta |— f inch long, 

 slender ; capsule small, narrow ; lid rostrate, oblique. Dioicous. 



Var. /3. heteropterum Schp. (Pterig. heteropterum Brid. in 

 part). More robust ; branches thicker, shorter, obtuse. Leaves 

 secund, rounded and apiculate at apex. 



Hab. Rocks and trunks of trees on mountains; rare. The var. /3 in more 

 shady situations. Fruit rare, summer. 



