APPENDIX 615 



P. 75. As to the Elatereae, there is great difficulty in dividing these 

 into distinct families. Cavers recognizes four families, viz., Aneu- 

 raceae (= Metzgeriea^), Blyttiaceae (= Leptotheceai), Codoniaceae, 

 and Calobryaceae ( = Haplomitreai). Of these the first two are almost 

 inextricably interrelated, and it will probably be best to combine 

 them into a single family. The family Codoniacea) contains a number 

 of genera which are very doubtfully related, e.g.,Pellia, Fossombronia, 

 and it will probably be necessary to remove some of the members now 

 included in the family, and perhaps to establish a new one. 



The Calobryaceae, comprising the genera Calobryum and Ilaplo- 

 mitrium, is a very natural one, but its relation to the other Jungerman- 

 niales is somewhat problematical. 



Stephani (i) states that he examined the original material of 

 Thallocarpus, and found it to be a Riccia. See also McAllister (i). 



P. 75. A recent revision of the genus Sphcerocarpus (Haynes (i) ), 

 shows that S. terrestris does not occur in the United States. The 

 plant from the Atlantic states hitherto regarded as this species is 

 apparently identical with S. Texanus, which in turn is not distin- 

 guishable from S. Californicus, which is united with that species. A 

 third species, S. Mans, has been discovered in Washington. See 

 also Douin (i). 



P. 86. Evans (3) has shown that in Metzgeria the gemmae arise in 

 essentially the same way as in Aneura, but the gemma remains 

 attached to the thallus until it has formed a multicellular body of 

 considerable size. 



P. S8. The genus Aneura, which is the largest among the An- 

 acrogynae, shows a good deal of variation in the form of shoot. Some 

 of the species, e.g., A. maxima, have a quite undifferentiated thallus 

 rivaUing in size the larger Marchantiales. Other species show a more 

 or less definite midrib, and still others, e.g., A. Tjibodensis, have much- 

 branched upright shoots arising from a prostrate rhizome, as in 

 Hymenophyton ( Umbraculum) ; but the branching is monopodial 

 instead of dichotomous. 



P. 88. In Pallavicinia the central portion of the midrib is 

 occupied by elongated fibre-like cells with markedly thickened cell 

 walls. 



P. 89. The antheridia in Pallamcinia {Mittenia) ZoUingeri are 

 borne on the midrib, each one being covered by a scale. In other 

 species, e.g., P. radiculosa, P. Levieri, they are in a row on either side 

 of the midrib, and are covered by a shelf-like outgrowth, which is 

 more or less continuous. (Campbell and Williams (37).) Calycularia 



