MIDDLESEX FLORA. 137 



A. Boottii, Tuck. (A. spinulosum, var. Boottii, Man.) 

 Maiden, Medford, Lowell, Ashby/et al. Not very common. 



A. acrostichoides, Swartz. CHRISTMAS FERN. 

 Common. The var. incisum, Gray, at Medford (Mrs. P. D. 

 Richards). 



CYSTOPTERIS, Bernh. BLADDER FERN. 



C. fragilis, Bernh. 

 Not uncommon. 



ONOCLEA, L. 



O. sensi bills, L. SENSITIVE FERN. 



Very common. The form known as var. obtusilobata is 



occasionally found. 

 O. Struthiopteris, Hoffm. (Struthiopteris Germanica, Willd., 



Man.) OSTRICH FERN. 



Maiden (F. W. Morandi) , but now probably extinct in this station ; 



Lincoln (G. E. Davenport) ; Bedford (L. L. Dame). Rare. 



WOODSIA, R. Br. 

 W. Ilvensis, R. Br. 



Not uncommon. 

 W. obtusa, To IT. 



Maiden and Melrose (F. S. Collins); Medford (L. L. Dame); 

 Chelmsford (Dr. C. W. Swan). Not very common. 



DICKSONIA, L'Her. 



D. pilosiuscula, Willd. (D. punctilobula, Kunze, Man.) 

 Common. 



LYGODIUM, Swartz. 



L. palmatum, Swartz. CLIMBING FERN. 



Concord (G. E. Davenport) ; West Newton (Severance Burrage) ; 

 Dracut (Dr. C. W. Swan) ; Groton (C. W. Jenks). Rare. 



OSMUNDA, L. 



O. regalis, L. FLOWERING FERN. ROYAL FERN. 



Common. 

 O. Claytoniana, L. 



Common. 

 O. cinnamomea, L. CINNAMON FERN. 



Common. The state called var. frondosa at Newton (F. S. 



Plympton); Medford (G. E. Davenport). 



OPHIOGLOSSUM, L. 



O. vulgatum, L. ADDER'S TONGUE. 



Maiden, Melrose and Concord (F. S. Collins) ; Newton (F. S. 

 Plympton) ; Chelmsford (Dr. C. W. Swan). Not common. 



