Hepaticce of North America. 



13 



HEPATIC^. 



5. Calyptra remaining be- 

 low at the base of the capsule 

 which ruptures its upper por- 

 tion. 



6. Capsule maturing before 

 rupturing the calyptra, open- 

 ing by 2 or 4 valves, or irregu- 

 larly; or indehiscent, never by 

 a special lid. 



7. Columella wanting (ex- 

 cept in Anthocerotacece). 



8. Elaters mixed with the 

 spores (except in Ricclacece). 



Musoi. 



5. Calyptra ruptured at the 

 base by the capsule, which it 

 covers as a cap. 



6. Capsule maturing after 

 rupturing the calyptra, open- 

 ing by a special lid (opercu- 

 lum). 



7. Columella always pres- 

 ent (at least at an early stage 

 of development). 



8. Elaters never present. 



In other characters the two groups closely resemble each 

 other. 



Subdivisions. The hepatics, varying so much in their 

 characters, may be arranged in four or five well-marked groups, 

 four of which it would seem should rank as orders^ notwith- 

 standing the rearrangement of recent European writers.* 



These four are all largely represented among our forms 

 and each is of somewhat general distribution. Their characters 

 may be arranged in tabular form for convenience of comparison : 



* Compare S. O. Lindberg Genera Europcea Hepaticarum secundum 

 novam dispositionem naturalem. In Acta Soc. Fenn. X. That Lindberg's 

 classification may be more widely known in this country a tabulated 

 outline will be found in Appendix B. 



