294 THK JOURNAL OF BOTANY 



(vol. 63, pt. 1) a very full and interesting account of ''The Her- 

 barium of John Dalton "' (1764-1848) which was acquired by the 

 Society in 1866 from the Manchester Public Library in whose 

 possession it had been since before 1864. "It seems to have been 

 almost entirely overlooked, and had unfortunately been allowed to 

 become exceedingly dirty and to some extent damaged by insects and 

 damp " : from the evidence adduced it would seem to be identical 

 with the collection which was in 1806 " m the possession of a Mr. T. 

 P. Heywood of the Isle of Man." A complete enumeration of the 

 contents of the herbarium is given, the introduction to which must 

 be consulted for its full desori]:)tion, and for an account of Dalton 

 himself, with references to the botanists with wliomhe was associated 

 and who contributed largely to the collection. Of the eleven volumes 

 in which the herbarium is contained, the first is dated 1790, the 

 plants in the seventh and eighth (part) were collected by Dalton in 

 1797 : the latest entry in the volumes is 1829. The authors of the 

 paper say : " There does not seem any evidence at all that Dalton 

 made two collections," and this, so far as regards the Manchester and 

 Isle of Man herbaria, is doubtless correct. But the Report of the 

 Yorkshire l^hilosophical Society for 1897 (p. xv) contains a note 

 transcribed from a memorandum in Dalton's hand in his copy of 

 Galpine's Compendium : " June 21st, 1827. Gave my Herbarium 

 and Coleopterous insects to the Philosophical Society of York " : 

 this herbarium (see Report for 1898, p. 36) contained " 2,500 speci- 

 mens of British Phanerogams " and is now in the Yorkshire Museum. 

 Dalton's plants figure largely in the somewhat extravagantly printed 

 " Catalogue of British Plants in the Herbarium " of the Society, the 

 publishing of which was begun in the Report for 1894 and was con- 

 cluded in that for 1917. 



A NEW edition (the fourth) of the Guide to the British Mycetozoa 

 exhibited in the Department of Botany has been " printed by order 

 of the Trustees of the British Museum " at the very reasonable cost 

 of a shilling. The following prefatory note by Dr. Bendle explains 

 the considerable changes which have been made in this issue : — "The 

 present edition has been carefully revised by Miss Gulielma Lister. 

 The publication of a new edition of the Monograph of the Mycetozoa, 

 in 1911, in which the nomenclature was brought into conformity 

 with the International Rules, has necessitated some alterations in the 

 names of genera and species in the present edition of the Guide. An 

 important advance in our knowledge of the life-history of the 

 Mycetozoa, to which reference is made in the Introduction, is the 

 discovery that the swarm-cells fuse in pairs and that the resulting 

 zvgote forms the plasmodium. Notes have been added to the Intro- 

 duction on methods of cultivation of the plasmodium and the swarm- 

 cells ; and on the collecting, preserving, and mounting of specimens. 

 The number of species recorded as British has been increased since 

 the date of the last edition, from 146 to 180; this increase indicates 

 the value of local work carried out by individual observers. An 

 innovation in the text is the noting under each species of the time of 

 year when the sporangia may usually be found in Britain ; and also 

 ithe derivation and meaning of the generic and specific names." 



