474 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 



in the fossil condition; and a sport or monstrosity, confined pre- 

 sumably to a small group of individuals or perhaps to a single 

 one, would have had a yet smaller chance. On general con- 

 siderations, therefore, it would seem most consistent to regard 

 our specimens as representing a species, and to apply a generic 

 name that will indicate merely a probable relationship with the 



ferns. 



Anomalofilicites monstrosus gen. et sp. nov. 



Size and shape of frond not known, the parts irregularly pinnate; 

 pinnae diverse in shape and size, mostly pinnatifid or obscurely 

 pinnate, linear-lanceolate in outline and tapering to the tips, but 

 occasionally expanded and pinnate except toward the base, the 

 pinnules pinnatifid. 



Tertiary (Fort Union Formation), Kern Ranch, Dawson County, 

 Montana. Collected by A. G. Leonard, George Holgate, and 

 W. H. Clark, September 28, 1906. 



Those who may be interested in the line of investigation sug- 

 gested by the peculiar surficial characters of these specimens will 

 find the following works of assistance: 



E. J. Lowe, Our native ferns, etc., vols, i and 2. London, 

 1867, 1869. 



Robert G. Leavitt, A vegetative mutant and the principle of 

 homeosis in plants. Bot. Gaz. 47: 30-68./. i-iQ. Ja, 1909. 



R. C. Benedict, Some modern varieties of the Boston fern at 



their source. Jour. N. Y. Bot. Gard. 16: 194-197. pi. 161, 162. 



S 1915. 



Explanation of plates 31 and 32 



Plate 31. Anomalofilicites monstrosus Hollick, natural size. i from U. S. Nat. 

 Mus. no. 34987; 2 from U. S. Nat. Mus. no. 34988; 3 from U. S. Nat. Mus. no. 34986. 



Plate 32. Nephrolepis exaltata (L.) Schott. Portions of heteromorphous fronds 

 from living plants growing in conservatory of the Brooklyn Botanic Garden, natural 

 size. 



