374 Bibliographical Notices. 



Linnseus from the imputation of having but imperfectly distinguished 

 between spina and aculeus. These errors have arisen from the cir- 

 cumstance that, in his 'Philosophia Botanica,' page 50, Berberis is 

 mentioned, together with Ribes, Rubus, and Rosa, as having aculei ; 

 and on page 110, Parkinsonia is instanced, with other leguminous 

 plants, as showing examples of aculei, although the thorns in these 

 plants must be considered as spinse, according to Linnseus' s own de- 

 finition in page 50. The only mistake of Linnseus is, according to 

 Mr. Didrichsen' s view, that Berberis has been mentioned (page 50) 

 amongst the examples of aculeus — a circumstance which is easily 

 explained when we remember that, when this part of the 'Philosophia 

 Botanica ' was written, Linnseus was slowly recovering from a dan- 

 gerous illness, as he states himself in the preface, and, while confined 

 to his bed, dictated this immortal work to one of his friends, as fast 

 as the printer could put it in type. Both at an earlier time, in the 

 ' Hortus Cliffortianus' (1737), and afterwards, in the 'Species Planta- 

 rum' (ed. 2. p. 472, 1762), he described the thorns of Berberis as 

 spina;. Whilst some over-zealous admirers of Linnseus have tried to 

 defend the excusable, but undeniable, error committed in p. 50 in the 

 • Philosophia Botanica,' others, misguided by a superficial similarity 

 between the thorns of Berberis and those of Ribes, have maintained 

 that the thorns of Ribes had also been erroneously mentioned among 

 the examples of aculei. Others, again, have entirely discarded Lin- 

 nseus's definitions, and attempted to find some new marks of distinc- 

 tion between aculeus and spina, derived from their position, the 

 constancy of their occurrence, and their development during the 

 growth of the plant. Mr. Didrichsen fully concurs with those who 

 reserve the name ofspince for such thorns as are only transformations 

 of the ordinary organs or parts of the plants, but describe as aculei 

 all thorns which are merely corticular appendages. But at the same 

 time he shows that Linnseus's definition in page 50 of the ' Philo- 

 sophia Botanica ' does in reality come to the same, and is the only 

 practically useful one. He shows that the difficulty which DeCan- 

 dolle thought to find in reference to the Monocotyledons does not 

 really exist, and that the investigations as to the development of 

 the thorns in Ribes Grossularia, by which some German authors 

 pretend to prove these to be spinse, are altogether unreliable. Nay, 

 Mr. Didrichsen even goes a step further. It is commonly supposed 

 that what are now called morphology or morphological points of view 

 were quite foreign to the mind of Linnseus, and that he only took 

 what we should call a terminological view of questions like the one 

 before us. But Mr. Didrichsen maintains that this was not the case. 

 Linnseus was the founder of botany as a science, and he was well 

 aware that the first thing necessary was to create a fixed terminology; 

 but it needs little explanation to show that for this purpose definitions 

 like those of spina and aculeus in p. 50 of the ' Philosophia Botanica' 

 were vastly preferable to definitions founded on morphological con- 

 siderations. Linnseus's description of Berberis in the ' Species Planta- 

 rum' (ed. 2. p. 470), in which he says, "folia in spinas tripartitas 

 mutata," as well as other passages, show that he knew quite well the 



