IIADULA. V3 



pair, erect if more, closely imbricate, bilobed to the middle, 

 antical lobe broadly obovate, lobule hardly half the size, subrotund. 

 Perianth projecting very much, slender, subincurved, trumpet 

 shaped, perfectly terete, only at the apex very sliglitly compressed, 

 mouth truncate, obsoletely 4-lobed. Androicia terminal on 

 branches ; perigonial bracts 2, 3 pairs, similar to the leaves only 

 lobule larger, slightly turgid, diandrous. 



Dimensions.— Stem ^ inch long, 'I mm. diameter, with leaves 

 1"25 mm. wide ; leaves, antical lobe 'S mm. x "6 mm., "65 mm. x 

 •55 mm., "7 mm. x "G mm., postical lobe or lobule 25 mm. x "3 

 mm., '2 mm. x "ITS mm., "3 mm. x "275 mm. ; cells '02 mm. x 

 •02 mm,, '03 mm. x '02 mm., '02 mm. x •0175 mm., "0175 mm. x 

 .0175 mm. ; bracts, antical lobe •G mm. x ^4 mm., postical lobe 

 •37 mm. X "35 mm.; perianth, 21 mm. x ^3 mm. (mouth) x ^15 

 mm. below the middle, 2' mm. x '35 mm. (mouth). 



Hab. — ^Extremely rare, the only known station being near 

 Tore Waterfall, Killarney, growing with Buniortiera irr'ujua, 

 Juhula Hutcliimice and Lejeunea Mackaii. G. A. Holt, June 

 1885; D. McArdle, 1897. 



Obs. — This distinct species cannot be confounded with any 

 other British ones ; from all it is distinguished by its smaller 

 size and slender habit ; R. germana, Jack, which is also dioicous 

 and somewhat slender, has larger and squarer leaf lobules, tlie fold 

 of which is not decurrent nor divergent from the antical lobe, and 

 the perianth being of a different shape and complanate. The 

 most important character of R. Iloltii, however, is the slender, 

 trumpet-shaped, terete perianth, sufficing to distinguish this 

 Radula from every other European species. 



Justly named by Dr. Spruce after its discoverer, Mr. Gr. A. 

 Holt, of Manchester, who is one of the most accurate students of 

 the British Mosses and Hepaticae. 



The description and notes are taken from Dr. Spruce's com- 

 munication to the " Journ. of Bot. " for July 1887. 



Description of Pj>atk XXIV. — Fig. 1. Plants natural size. 

 •2. Portion of stem, antical view, x 24. 3. Ditto, postical view, 

 X 24. 4. Portion of branch, postical view, x 24. 5, 6. Leaves, 



