TortulacejE.] 187 [Acaulon. 



Hab. — Fields and by ditches, rare. Fr. 10 — 12. 



Near Croydon {Dickson) ! Bedford purlieus, Wansford {Berkeley 1827) ! Hurstpier- 

 point (Mitten 1846) ! ! Near Marsden, Durham {Bowman 1840) ! Ditchling, Sussex 

 {Davies i86g) ! ! Buckingham {Holmes 1876) ! ! Wrotham, Kent {Holmes). 



The calyptra is so variable in the different species, that it is quite insuffi- 

 cient to characterize a separate genus Ephemerella, 



2. ACAULON C. MuELL. 



(Hot. Zeit. 1847, p. gg.) 



Plants minute, gemmiform, gregarious. Capsule immersed, globose, 

 not apiculate. Calyptra conic, very small, resting only on the top of 

 caps, torn irregularly. Columella thick. Spores minutely granulose. 

 Leaves tristichous, upper very large, concave, connivent. — Der. « neg. 

 KttvXos a stem. 



Clavis to the Species. 



Perich. bracts convolute, nerve vanishing at point. miiticum. 

 ■ boat-shaped, carinate, nerve excurrent. triquetyum. 



I. ACAULON MUTICUM {Schreb.) C. Mmll. 

 Autoicous ; bracts broadly oval, concave, subconvolute, the nerve 

 vanishing in apex. Caps, erect on a straight pedicel. (T. XXVII, G.) 



Syn. — Phascttm acaulon R. minus L. Sp. pi. 1570 {1753). HuDS. Fl. angl. 3g7 (1762). Weiss 

 Cr. goett. 267 {1770). Ehrh. Han. mag. 1780, p. 235. 

 Phascimi muticiim Schreb. de Phasco obs. 8, excl. syn. t. 1, fgg. 11-14 (1770) ; Spic. fl. lips. 

 73 (i77^)' Web. Spic. Fl. goett. 126 (1778). Hedw. Fund. muse. II, 85 (17^2), Sp. 

 muse. 23 {1801). Roth. Fl. germ, i, 452 (1788). Timm Fl. meg. 11. 7ig {1788). Jacq. 

 Collect, ii, 215 (1788). SwARTZ Muse. suec. 18 {i7gg). Hoffm. Deutsch. Fl. ii, 21 

 (i7g5). With. Bot. arr. br. Veg. 3 ed. iii, 784 (i7g6). Hull Br. fl. P. 2, 251 (i7gg). 

 Brid. Muse. rec. II, P. I, 10 {1798), Sp. muse. I, i (1806), Mant. 4 (i8ig), Bry. univ. i, 

 22 {1826). RoEHL. Moosg. deutsch. 15 (1800), Deutsch. fl. iii, 32 (1813), Ann. wett. 

 ges. i, 187. Sm. Fl. br. iii, 1156 (i8oi). Eng. bot. t. 2027. Turn. muse. hib. 3 (1804). 

 P. Beauv. Prodr. 82 (1805). Schultz Fl. starg. 271 {1806). Web. Mohr Bot. Tasch. 

 69(1807). ScHKUHR Deutsch. kr. gevif. P. 2, 10, t. 4 (1810). Schwaeg. Suppl. I, P. I, 

 2 (1811). Mart. Fl. cr. erl. 125 {1817). Hook. Tayl. Muse. br. 8, t. 5 (1818). Funck 

 Moost. 2, t. I (1821). Gray Nat. arr. br. pi. i, 712 (1821). Hook. Fl. scot. P. II, 122 

 (1821) ; Br. flora ii, 3 (1833). Nees Hornsch. Bry. germ, i, 46, t. 5, f. 5 (1823). Br. 

 ScHiMP. Bry. eur. fasc. i, p. 8, t. 2 (1837). Hueben. Muse. germ. 8 (1833). Rabenh. 

 Deutsch kr. fl. ii,s. 3, 81(1848). Wils. Bry. br. 29, t. 5 (1855). Mack. Fl. hib. P. z, 

 8 (1836). HoBK. Syn. br. m. 27 (1873). HusN.mouss. nord-ouest. 34 (1873). 



Phase, btdbosum VoiT Muse. herb. 8 (1812). De Not. Syll. muse. 305 (1838). 



Ephemerum muticum Hampe in Flora xx, P. I, 285 (1837). 



Acaulon muticum C. Muell. in Bot. zeit. v, gg (1847). Syn. muse, i, 22 (i84g). Br. 

 ScHiMP. Bry. eur. fasc. 42, Suppl. mon. 3, t. i (1849). Jaeg. Ber. St. Gall. ges. i86g, 

 p. 75. HusN. Mousses n. o. 2 ed. 57 (1882). 



Schistidium muticum Mitt, in Ann. mag., Nat. Hist. 1851, p. 311. 



Sphcerangium muticum Schimp. Synops. 13 (i860). Berk. Handb. br. m. 302 (1863). 



LiNDB. de Tort. 216 (1864). Milde Bry. siles. gi (i86g). Juratz. Laubm. oester.- 



ung. 88 (1882). Lesq. James Mosses N. Amer. 40 (1884). 



Autoicous ; dull green gregarious, gemmiform, oblong conic, 

 rounded-triangular. Leaves few, broadly ovate, very concave, un- 

 dulated ; perich. bracts two, much larger, subconvolute, not keeled, 

 suddenly narrowed into an eroso-denticulate point, nerve vanishing at 



