Moore — 0/i the Mosses of Ireland, 
375 
2. D. Tiomomallum (Ilampe), Linnsea, 1847. Leptotrichum homo- 
mallum, Miiller, Synop. Muse, p. 1453. Schimp. Synop. Miis- 
cor., p 143. Rabenhor., Bryothec. Europ., No. 663. Tri- 
chostomum homomallum, Bryol. Europ., vol. ii. Monojyr., 
p. 16, tab. 181. Bryol. Brit., p. 116, tab. 20. Didymodon 
heteromallum, Museol. Brit., Ed. 2, p. 119. 
Hab. Among heath and on sandy and clay banks. Frequent in the 
hilly counties of Ireland, and all round the coasts, but rather 
rare in the central counties. 
4. D. jiexicaule (Hampe), 1. c. Leptotrichum flexicaule, Miiller, 
Synop. Muscor. 1, p. 449. Schimp., Synop. Muscor., p. 144. Ra- 
benhor., Bryothec, Europ., Tio. 423. Trichostomum flexicaule, 
Bryol. Europ., vol. II. Monogr., p. 15, tab. 180. Bryol. Brit., 
p. 116, tab. 42. 
Hab. On sand-hills near the sea, and on dry rocky places inland. 
Abundant at Portmarnock and Malahide, Dublin; Arklow, 
"Wicklow ; Killala, Mayo ; Benbulben, Sligo, and many other 
parts of Ireland, but always barren. 
Sect. 5. TortulcB. Peristome of 32 teeth, mostly long and more or 
less contorted from left to right. 
34. ToRTULA (et Barbula.) Hedw. 
Calyptra often elongated, cleft at side, or cuculliform. Capsule 
ovate-oblong, or subcylindrical, long pedicellate. Peristome 
single of 16-32 filiform, more or less contorted teeth, united 
at base into a short or long membranous tube ; rarely without 
teeth. Leaves very various in form, with nerves short or long ; 
sometimes excurrent into a mucro, or piliferous ; areolation dense 
in upper part of leaf; basal cellules larger and diaphanous. 
JSTearly allied to Trichostomum ; differing principally in the tor- 
sion of the teeth. 
Diagnosis of Species, 
a. Leaves with accessary lamellae on nerve, 1 . T. lamellata. 
aa. Leaves with filamentous excrescences on the upper side of nerve. 
Leaves with margins incurved to their 
points ; calyptra small, covering half 
the capsule, 2. T. rigida. 
Calyptra small, covering little more than 
the lid, . . . . . . 3. T. ambtgua. 
