THh MUONWORT AND ITS ALLIES. 55 



The triangular, much divided blade and heavy fruiting 

 panicle of this species gives it considerable superficial 

 resemblance to the rattlesnake fern but there is little 

 chance that they will be confused in the field. The 

 rattlesnake fern has shed its spores and the fertile part 

 has withered and gone, long before the grape fern has 

 thought of coming up. Of all our species, this is latest 

 to appear. Often it does not start into growth until 

 late in July and the spores are not ripe until September 

 or October. It also has the distinction of being our 

 only evergreen Botrychium. At the approach of cold 

 weather the fertile portion decays while the sterile merely 

 takes on a rich bronze hue and braves the frost and 

 snow. In late fall and early spring it is quite con- 

 spicuous and the collector often locates his specimens at 

 such seasons, returning later to collect them. The old 

 frond usually remains until the new one has developed, 

 just as that of the rattlesnake fern does, further south. 



The grape fern is from six to eighteen inches in height 

 and quite fleshy. The blade approaches the triangular 

 in outline and springs from the common stalk near the 

 base. It is itself long stalked, the latter feature serving 

 to distinguish it from its allies in northeastern America. 

 There are six or more pairs of stalked pinnae each of 

 which is again pinnate with lobed or incised pinnules. 

 The blade is frequently described as ternate, because the 

 lowest pair of pinnae are nearly as large as the rest of the 

 frond. The pinnules and segments are quite variable in 

 shape and cutting and these differences are often con- 

 sidered of sufficient importance to warrant the making 

 of numerous varieties or even species. The sterile part 

 of the frond spreads nearly horizontally but the fertile 

 is much taller and quite erect. The latter is about three 



