m u s c i. 95 



and 1-2 lines wide, more or less resupinate and compressed, subpin- 

 nately branched ; the branches short, slender, not crowded. The 

 leaves rather loosely imbricating, erect-patent, ovate or oblong-lanceo- 

 late, moderately concave, substriate uneven; margins narrowly 

 reflexed, slightly serrulate at the point; costa reaching nearly half 

 way ; areolation of minute subrhombic cellules. Investing the secon- 

 dary stems at the base of the leaves are minute, variously shaped 

 paraphyllia. Leaves of the branches smaller and narrower. Peri- 

 chsetia long and slender, situated on the upper part of the secondary 

 stems. Capsule oblong-cylindrical, straight or slightly curved, exan- 

 nulate. Pedicel short, mostly concealed by the long, filiformly acu- 

 minated perichsetial leaves. Calyptra smooth, dimidiate, narrow, 

 extending below the middle of the capsule. Operculum conic, with 

 a long slender rostrum. Teeth of the outer peristome linear lanceo- 

 late, attenuate, distantly articulated, with a distinct median line, 

 below yellowish striolate, above grayish-white, scabrous; cilia of 

 the inner peristome nearly as long as the teeth, subulate, nodosely 

 articulated, punctulate, arising from a narrow plicate membrane; 

 ciliolge none, or rudimentary. Dioicous: male plants intermixed 

 with, and about the size of the fertile; branches longer and more 

 spreading. Perigonia numerous, large, and conspicuous, placed 

 closely together in two lines, one on each side of the stem. Anthe- 

 ridia 4-6, paraphysated. 



This species has strikingly the aspect of Lasia tricliomitrion, but its 

 smooth calyptra, double peristome, and dioicous inflorescence, show it 

 to be not only specifically, but generically distinct. 



Plate 25. — Alsia California : male and female plants, of the 

 natural size. Fig. 1. Portion of a stem, with mature fruit. 2, 3, 4. 

 Stem-leaves. 5, 6. Lower and upper parts of leaf, showing the reti- 

 culation. 7. Cellules of the same. 8. Cross-sections of a leaf. 9, 

 10. Branch-leaves. 11. Capsule and perichaetium. 12. Capsule, 

 with operculum. 13. Deoperculated capsule. 14. Peristome, with 

 portion of capsule. 15. Portion of outer and inner peristome, with 

 spores. 16. Vertical section of peristome. 17. Calyptra, 18. Peri- 

 chaetial branch, vaginula, archegonia, paraphyses, and portion of 

 pedicel. 19, 20. Perichaetial leaves. 21. Male bud. 22. Male bud 

 in the axil of a leaf. 23. Male flower. 24. Antheridium and para- 



