53 



33. BOTRYCHIUM TERNATUM SwartZ. 



Ternate Grape Fern. 



The Botrj'chiums form one of the most interesting genera of ferns 

 we Iiere have represented. There are but ten recognized species of 

 Botrychium linovvn in the world, seven of wliich grow in America. 

 Our two larger forms are very distinct, but the smaller ones seem to 

 run into each other, though there are distinctions not at once notice- 

 able to a casual observer. B. ternatum lias two perfect fronds, one 

 sterile and one fertile, distinct to the ground. The typical form is 

 found in California growing to great size, while here the fertile frond 

 seldom exceeds ten inches in heiglit, with a sterile frond five inches 

 across. Found at Essex, 1872-4. 



3-1. Var. lunarioidcs has more rounded segments than the typical. 

 The finest specimen I ever saw was found by Mrs. Horner, in George- 

 town. 



35. Var. obliquum. The segments are longer, and are quite oblique 

 to the rachis. 



36. Var. dissecCum. The whole frond is cut and recut till almost 

 entirely reduced to points. Nos. 3i, 35, 36, are found both in wet 

 shady places, and in pastures. 



37. BoTRYcniUM VinGiNiANUM Swartz. 

 BattlrsnaJce Fern. 



Found in Beverly, and also in Georgetown (Mrs. Horner). This 

 beautiful and delicate fern is the largest of all the Botrychiums and is 

 found from Canada to the tropics. Not rare, yet (owing to its never 

 spreading except by spores) it is seldom found abundant except as a 

 number of specimens scattered through the woods. In this the fertile 

 spike is on the same stalk with the sterile frond, all the limbs spring- 

 ing from a common centre much above the ground. There are one or 

 two of the small species of Botrychium which possibly may be found 

 in the county. 



FER.VS THAT POSSIBLY MAY YET BE FOUND GROWING 

 NATURALLY IN ESSEX COUNTY^ MASS. 



1. WooDWARDiA ANGUSTiFOLiA Smith. Now fouud in Hinghara 

 and Dedhara. 



2. rHKGorTEUis HEXAGONOPTERA Fee. Fouud in Portland, Brattle- 

 boro and South. 



3. AspiDiUiM CRiSTAxmi var. Cltntoxianum D. C. Eaton. Fouud in 

 Vermont and New Hampshire. 



