u 



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All these collections are now in charge of the Botanical Section 

 of the Academy. Their chief value lies in the large number of 

 species from early collectors, and of type specimens of early authors. 

 Most of Nuttall's early species' are deposited here and have been 

 the vouchers used by Torrey and Gray in deciding upon their specific 

 validity, Schweinitz's own types of his new fungi, lichens, etc., 

 are here, as well as many of the types collected by Bigelow and 

 others in the Whipple Exploration, bearing tickets in the beautiful 

 chirography of Dr. Torrey. 



So old a collection, much of it running back for sixty or seventy 

 years, might be expected to have suffered from the ravages of insects, 

 and from the crumbling effects of time. Some portions have, indeed, 

 thus suffered, but careful attention and thorough poisoning have kept 

 this destruction within narrow limits. Many of the species from 

 tropical regions have remained undetermined, and are in fragmentary 

 condition. Dependent as the Academy has mainly been, upon vol- 

 unteer and occasional supervision, it has been impossible fully to 

 determine all new accessions, or even properly to care for the old. 

 All should be carefully worked over, the redundancies sifted out, 

 the hiatuses filled, and the work of mounting carried on to comple- 

 tion. It may be hoped that ere long some public-spirited individual 

 will be incited to make an endowment that shall provide for this and 

 other needed botanical work. 



It is always difficult to ascertain the number of species in a large 

 herbarium, and estimates are apt to be excessive. In collections 

 received from many sources, there will of course be a large amount 

 of duplicating. Doubtful, imperfect and undetermined specimens 

 increase the difficulty, and the varying ideas as to the true circum- 

 scription of specific limits add another element of doubt. The 

 . Academy*s Herbarium has been estimated to contain as high as 

 70,000 species, an estimate made doubtless without proper regard to 

 the large number of species common to the several collections of 

 which it is made up. Recent estimates, based on portions which have 

 been carefully worked over, would give the number as not less than 

 40,000, nor more than 45,000 species. 



In preparing this notice, free use hasbeen made of the history of the 

 Academy's progress and condition, prepared by Dr. Ruschenberger, 

 who has been for nearly fifty years one of its most active members, 

 and for the last eleven years its presiding officer. 



J. H. R. 



i 3^- Rooting at the Tips of the Branches.— According to A^a- 



fure of Dec. 23d, Francis Darwin read a paper before the Linnean So- 

 ciety, Dec. i6rh, on " The Theory of the Growth of Cuttings, illus- 

 trated by Observations on the Bramble, Rubus fruticosusr His ex- 

 periments indicated that root-budding took place generally at or 

 near the tips or distal ends, rather than at or near the basal ends of 

 the branches, and he evidently deduce's therefrom the fact that for 

 the plant it is better that it should perpetuate itself Dy thus rooting 

 at the tip-ends of the branches. As this is so contrary to the belief 

 and the practice of all horticulturists, I think one should hesitate to 



