170 FETCH : 



to six millimetres m diameter. This increase is produced by 

 closely packed lamellse which project horizontally from the 

 arm over the whole of its surface, except along the median line 

 on the exterior side. The. gleba-bearing tissue thus covers the 

 inner surface and side of the arm, but leaves free a narrow 

 median furrow externally : and as the sides of adjacent arms 

 are usually in contact these median f uitows are more evident 

 than the divisions between the arms. Watson's figure, and 

 also Berkeley's (copied by Fischer),- emphasize these furrows 

 and omit the lines which distinguish the separate arms. 

 The most evident line on the photograph is a median furrow. 

 The furrow widens out above and below, and makes it appear 

 at first sight as though the gleba were an additional thick 

 oblong sheet with the corners rounded off, wrapped round each 

 arm but not quite meeting exteriorly. 



The sporiferous portion appears granular, like the head of 

 Dictyophorairpicina, and it is somewhat wrinkled transversely. 

 Slight magnification shows that the granular effect is produced 

 by the plicate free ends of innumerable processes. In cross 

 section these are seen to consist of numerous thin lamellae 

 which project from the thin wall of the central tube, except 

 along the external median line. The wall of the tube is in- 

 folded beneath the furrow thus left, and the cavity is slightly 

 reniform in section. These lamellse arise usually from a 

 narrow base and expand outwards. Most of them are divided 

 or branched in the outer half, and the outer edge is usually 

 plaited. The bases lie somewhat regularly in horizontal rows 

 round the arm, and the lamellse near the points of origin are 

 entirely in the same horizontal plane, but towards the outer 

 extremity a lamella may be irregularly folded or even bent 

 round upon itself. In dissecting out a ring of lamellae, these 

 folds are more or less flattened out , and the whole appears as 

 a frill round the central cavity of the arm. The lamellse are 

 only a few cells thick, except at the outer edge : here they 

 become about twice as thick, and are darkened with the gleba, 

 which penetrates between them. The structure is similar to 

 that of Dictyophora irpicina, and as in that species the gleba 4s 

 scanty. The herbarium specimens collected by Thwaites have 

 the same structure. The gleba is absent from the upper three 



