154 NATURAL SCIENCE. March. 



The Meaning of a Species. 



In the Botanical Gazette for December, 1896 (vol. xxii., pp. 454- 

 462), Professor L. H. Bailey has a suggestive article on " The 

 Philosophy of Species-making." Discarding Cuvier's conception of a 

 species as " the reunion of individuals descended from one another, 

 or from common parents, or from such as resemble them as closely as 

 they resemble each other," no less than the older conception of a 

 species as a unit of creation, he attempts to show that a species is a 

 purely subjective idea, and consequently defines it as : " The unit in 

 classification, designating an assemblage of organisms which, in the 

 judgment of any writer, is so marked and so homogeneous that it can 

 be conveniently spoken of as one thing." 



This way of regarding a species involves inevitable consequences. 

 First, extreme splitting : " I look with favour upon the tendency to 

 make specific names for forms which have heretofore been regarded as 

 well marked varieties." Second, arbitrariness: "Species are judg- 

 ments," said Asa Gray ; " I would not for a moment make it a test of 

 a species that there should be no intergradient forms," says his pupil. 

 Third, the exaltation of the species-spotter, the name-lover, the 

 museum mind : " Species-division will be useful in proportion as it is 

 founded upon obvious and easily ascertained attributes" ; " it is not 

 necessary, or even desirable, that we should search for obscure 

 or anatomical characters with which to separate them. These 

 characters belong to anatomy, physiology, embryology, and the like, 

 not to taxonomy." No "physiological species " for Professor Bailey ! 



We quote this article because the views of a clever and 

 experienced man on such a subject are always of interest. But we 

 cannot agree to this separation of taxonomy from the other branches 

 of biology, nor can we hold that expediency is everything. The last 

 time we quoted an American botanist at length we were accused by 

 an eminent though anonymous geologist of "endorsing" pernicious 

 opinions, insulting to our supporters. Professor Bailey's views would 

 perhaps please our critic ; we must therefore explain that we do not 

 endorse them. 



A Pine and its Fungus. 



In the same number of the Botanical Gazette, Mr. B. T. 

 Galloway describes the action of a rust-fungus occurring on the leaves 

 of the scrub or Jersey Pine {Finns Virginiana) and causing the plant to 

 cast its leaves. This result is known to follow the attacks of a 

 number of fungi, and in this particular case Mr. Galloway has made 

 an interesting series of observations on the course of events in the 

 leaves affected. During the winter the leaves of the pines, in common 

 with other evergreens, change colour, the dark green giving place to 

 orange as the season advances. With the approach of spring the 

 normal colour is resumed, growing brighter as conditions become 

 more favourable. In early May those affected by the fungus (a 



