THE imi'ITLE BLADDKi: KliUN. 



confined dampness generally maintained in structures where ferns are grown, but as wo line] native 

 Specimens from Ben Lawcrs and from Ireland are similarly affected, it would appear to bo a natural 

 parasite of these tender herbaceous ferns. 



The most remarknMe forma differing from the ordinary typical Brittle Bladder Fern, are the 

 following ; which are, however, not always so well defined as could he wished : — 



1, angustaUi (Smith). Tho form to which this name has been given appears to be one of the larger 

 states of the specie**, and includes those forma in which the edges of the smaller pinnules, and of the 

 lubes uf the larger ones, are deeply and rather evenly incised into conspicuous longish narrow teeth. 

 According to Sir J. E. Smith this is the same as the Puty/mltum rlucttvum of Dickson ami of Bolton 

 {FiL Brit, t. 45). Tho spores (in Dickson's plant) are roundish and echinate. Mr. Wollaston and 

 011101*8 think it is not a very constant form, and probably there are more than one to which the name is 

 applied, some of which may revert under culture to the ordinary state; but wo have a plant smaller 

 indeed than Smith's description seems to point out, which we include under angnstuta, ami this with 

 us is quiet constant under cultivation. It is more attenuated in the frond, the pimue, and tho pinnules ; 

 and these are its chief characteristics. 



% obtma (31.). This is a distinct and constant form, cultivated by Mr. A, Tail, of Edinburgh. It is 

 peculiar in its short blunt ovate narrowly and shortly stalked pinnules, which arc deeply separated 

 into distinct oblong lobes, almost pinnules, and these are notched with small even teeth, which are very 

 apparent The spores are cchmate. The colour of the fronds is a dark green. 



3. dmlnta (Dickson). There are some cultivated forms referable to this variety that arc constant, 

 though it is probable that accidentally blunt pinnuled fronds of other forms arc sometimes associated 

 with it in the herbarium, and hence it is often looked on as inconstant The features of tho true plants 

 are, small size (four to eight inches long), and confluent pinnules, so that the narrow fronds arc sometimes 

 scarcely bipinnate ; these pinnules arc blunt-oblong, simply blunt- toothed, or obscurely blunt-lobcd, and 

 with the sori placed near their margin. Somewhat larger and more deeply lobed forms, having the 

 same aspect, are met with, and through these it gradually merges into obtu&t, and the normal form. 

 The spores arc echinate, but scarcely in so marked a degree as they are in G.fragUu itself 



4. decutrms (M.), A variety intermediate in aspect between dmUUa aud Dickiettna, approaching 

 the latter in the decurrent pinnules and deflexed pinmc, but different in tho more acute apices of the 

 fronds and pinnules, and in the more erect and prominent teeth, which rather resemble the former, as 

 docs the colour and texture- The spores are echinate. It was found by Mr. Tait, on the coast 

 Of Kifcshire. 



5. Dickieana (Sim). The most marked in habit of all the known forms, but connected with fraffitif, 

 through decurrms and detUata, and therefore only to be considered as a variety. Its peculiarities 

 consist in the deflexed pinna; more or less overlapping, and in the crowded overlapping position of the 

 broad short obtuse bluntly-toothed pinnules, which are all connected by the wing of the rachis in 

 which they arc decurrent The colour is uniformly a deep bright given. In the more highly 

 developed of the fertile fronds the lobes of the pinnules, though still blunt, arc more distinct, and they 

 have then blunt inconspicuous teeth. Hie sori are situated very near the margin, The pinna; arc 

 twisted more or less from the plane of the frond, as occurs in some degree in dentata, from which, with 

 the deflexion of the pimue and the frequent confluence of the pinnules, results a pecular aspect, by 

 which this variety is known at first sight. The spores are slightly vcrracato or tuberculatc, not 

 echinate- tubcrcu late as in the other varieties, a fact, wc believe, lirst pointed out by Mr. Wollaston. 

 The plant was first found by Dr. Dickie on dripping rocks in a cave at Cove, near Aberdeen, and it 

 has since been gathered in the same place by several botanists, and by Dr. Balfour, near Dunkcld. In 

 cultivation this sometimes produces fronds or pimue, with the apices multiful. 



6. multifida (\V\). In this, which is not permanent the apices of the pinnae or of tho frond arc bitid 

 or multiful, or the stipes is divided. 



