264 Alexander W. Evans, 



ginal cells to M. nepalensis, M. nitida, and M. tholophora, while 

 he states that the cells of M. paleacea are subequal in size, a 

 specific difference which is not supported by actual comparisons. 

 When contrasted with the appendages of M. polymorpha, those 

 of M, paleacea are seen to be narrower, usually less toothed, and 

 composed of larger cells, which show a less marked decrease 

 in size between the median and marginal regions. 



The male receptacles of M. paleacea seem to be infrequent. 

 In the few cases seen the receptacles have been remarkably like 

 those of AI. polymorpha, although borne on shorter stalks. In 

 other words the disc has been shortly eight-lobed with rounded 

 rays and narrow sinuses. According to Schiffner the rays as 

 they grow older become longer and give the disc a palmate 

 appearance. If this is true the male receptacles exhibit a con- 

 siderable range of variation. The cupules of M. paleacea, with 

 their dentate, sharp-pointed lobes, likewise agree with those of 

 M. polymorpha and its allies, except that the outer surface is 

 free from epidermal papillae. 



When well developed the female receptacle of M. paleacea 

 consists of a disc with nine horizontal flat rays borne on an 

 elongated stalk. In many cases the rays are about twenty degrees 

 apart and present the appearance of being symmetrically 

 disposed. Even here, however, the single plane of symmetry 

 is marked by the sinus between the two basal rays, which is much 

 deeper than the others. When the basal rays are separated by 

 a sinus more than twenty degrees wide the plane of symmetry is 

 more apparent and the disc does not show a radial appearance. 

 Since the width of the sinus between the basal rays varies 

 markedly it should not be made the basis for specific separations, 

 although this has evidently been done in the past. The extremi- 

 ties of the rays are variously dilated and are truncate or even 

 emarginate at the apex. In the center of the disc the hemi- 

 spherical or bluntly conical protuberance is usually distinct, and 

 the same thing is true of the nine rounded ridges extending from 

 the protuberance to the beginnings of the rays. When the recep- 

 tacle is young or, in some cases, when fertilization has not taken 

 place, the rays do not spread horizontally but extend downward, 

 and usually, under these circumstances, the median protuberance 

 and the radiating ridges are only slightly developed. In fact 

 they are not always distinct even when the rays have assumed 



