348 Transactions. — Botany. 



natural sequence under one tribe or subtribe, tbe few characters which at 

 present define the genus would be sufficient for the higher group, in accord- 

 ance with the law enforced by Jussieu, that the larger the group the fewer 

 the characters by which it is limited. What reasonable objection can be 

 urged to the proposal. We should outrage no natural alliance of the 

 species. While the advantage would consist in this, that the name of each 

 lichen would carry with it not only the tribal characters but also its dis- 

 tinguishing generic characteristics, and would thus secure to the student 

 one of the leading objects of a natural classification. 



It is urged that to scatter cognate species amongst a number of genera 

 would be an offence against the harmony that exists in nature ; but if so, and 

 we are to be governed by mere prudery, no division of species could be ad- 

 mitted, seeing that, as Eay asserted and Linnaeus copied, " Natura non facit 

 saltus.'' , Indeed, there is no scheme of classification which is not liable to the 

 objection that between two closely-allied genera there will always be one or 

 more species which can be placed in either of the two ; and, as Lindley 

 observes in "The Vegetable Kingdom," — "it cannot be of any possible con- 

 sequence whether an intermediate or frontier plant be assigned to one 

 group or another and convenience alone should be considered in such a 

 matter. * * * All the groups into which plants are thrown are, in one 

 sense, artificial, inasmuch as Nature recognizes no such groups. Neverthe- 

 less, consisting in all cases of species very closely-allied in nature, they are 

 in another sense natural. But as the classes, subclasses, alliances, natural 

 orders and genera of botanists have no real existence in nature, it follows 

 they have no fixed limit and consequently it is impossible to define them." 

 That differences exist among the Lecidece as now constituted sufficient for 

 the purpose of arranging the species under several genera is certain from 

 the success which appears to have attended the labours of Massolonga and 

 others. Nylander himself has arranged them in sections. As to the ques- 

 tionable value of Massolonga's scheme, I do not at present wish to make 

 any remarks, or to criticize Nylander' s sectional arrangement. 

 1. Bmomyces novce-zealandics, n. sp. 



Thallus crustaceus tenuissimus sordide luteolus, madefactus albo- 

 virescens, effusus pulverulens (microscopi area granula gonima obsita). 

 Apothecia discoidea peltata, in centro peranguste adnata (diam. circa 

 2 mm.) madefacta albo-incarnata et convexa, margine obsoleto, excipulo 

 proprio incolorato arachnoideo-filamentoso (fills diam. 0-001 mm.), para- 

 physibus tenuissimis densatis paucis apice laxis nonnihil ramosis. Sporae 

 in ascis cylindraceis angustissimis confertissimis uniseriales oblongo-sub- 

 fusiformes incolores simplices, guttam unam magnam (evanescentem 

 glycerina) centralem continentes, longit. 0*017 mm., crassit. 0*006 mm. 



