190 ENGLISH BOTANY. 



so as to be almost spherical ; usually about £ inch in diameter, and 

 have the bracts tapering and acute, as are also the branchlets of the 

 barren whorls. The most important difference, however, seems to be 

 in the shape of the nucules, which are much more globose in N. intri- 

 cata than in N. glomerata. 



Of var. prolifera I have seen no specimens, either British or foreign ; 

 except by its larger size, and simple barren branchlets, it seems 

 un distinguishable from N. intricata. 



Many-fruited Nitella. 



EXCLUDED SPECIES. 

 NITELLA NIDIFICA. Agardh. 



In the report of the Botanical Exchange Club for the year 1867, 

 published in 'Journal of Botany' for 1868, at p. 73, Mr. Baker 

 writes, " A plant gathered many years ago by Dr. Moore in Lough 

 Neagh, and suspected by him at the time to be the true Cham 

 nidifica of the Fl. Danica, may not unlikely prove to be really so. 

 It has been submitted to Dr. Braun for his opinion, and his reply 

 is, " Habitus et folia omnino nidijica?, sed seminibus minoribus magis 

 contortis accedit ad C. fasciculatum (intricatum)." I do not know 

 if Messrs. Groves have seen this plant, or if it has been found by 

 any other botanist except the late Dr. Moore. 



[Of the Lough Neagh plant mentioned above, there exists in the 

 Kew Herbarium but one specimen, on which Prof. A. Braun has 

 written as above quoted, and in his 'Fragmente Monographie 

 Characeen,' p. 94, he writes of this specimen as follows (transla- 

 tion) :—" Habit of the Baltic N. nidifica, the leaves of the fertile 

 whorls incurved in the same manner and obtuse. Nucule smaller, 

 more contorted, 10-gyrate, unripe, 0,46-0,48 mm. long, without the 

 crown 0,43-0,44 mm. long, nucleus yellowish-green 0,30-0,35 mm. 

 long." He also says that it is " a form which would seem best 

 united with N. intricata and prolifera, or rather with N. glomerata." 



A very careful examination of this specimen with N. nidifica and N. 

 glomerata, however, has not corroborated what Braun has stated. A 

 comparison under the microscope, side by side with typical specimens 

 of N. nidifica from the Baltic, named by Professors Braun and Nord- 

 stedt, has failed to disclose the least difference between them. The 

 nucules examined by Braun must have been quite immature ones, 

 which are the most numerous on the specimen, but there are a few 

 which appear to have attained their full growth, and these are neither 

 smaller nor more contorted than those of N. nidifica, and appear to 



