628 



SCIENCE. 



[N. S. Vol. XV. No. 381. 



Giacosa, of Turin, to accompany his recent 

 edition of certain of the Salernitan masters 

 ('Magistri Salernitani,' Turin, 1901). 



Early plant drawings give their chief at- 

 tention to outline; particularly of leaves, stem 

 and branches. Flowers were less often and 

 less successfully indicated. The character- 

 istic Itahit of a plant, however, was often 

 caught very perfectly. Figures were copied 

 often with scrupulous care from one manu- 

 script to another. Several causes tended, 

 however, to their degeneration. Pliny charges 

 the blame for the imperfect plant-figures of 

 his time upon lack of skill of copyists. Some 

 of the worst among later errors were those 

 of copyists who had never seen the plant and 

 who were attempting copies of plants of dis- 

 tant regions as in early Anglo-Saxon figures 

 of Aster and other classic plants. In other 

 copyists a desire for balance and symmetry 

 overcame their fidelity to the original, so that 

 they conventionalized their plants; as seen 

 strongly in later Italian work exhibited, de- 

 veloped in the fourteenth century from the 

 Salernitan school; and as retained in early 

 printing, Italian woodcuts of 1499 inheriting 

 the same tendency. A fourth source of error 

 in plant-figures was the mediaeval love of the 

 marvellous, so that many copyists outdid 

 their text in depicting fictitious monstrosities, 

 as in the fifteenth century pictures of man- 

 drakes, Tartarian lamb, etc. 



Some of the earliest plant-figures of which 

 we know were those made by Cratevas, Greek 

 physician to Mithridates, about 100 B.C. 

 Something of their character and form prob- 

 ably still survives to us in certain illustrated 

 manuscripts of Dioscorides, of the fifth cen- 

 tury, with figures evidently copied, not from 

 each other, but from an earlier common source. 

 There is great need in the interests of the his- 

 tory of botany, that the project of publishing 

 the figures of the Anician Vienna codex, now 

 laid aside for nearly two centuries, should be 

 revived and carried to successful issue. In 

 the discussion following this paper Dr. Brit- 

 ton, Dr. Underwood, Professor Lloyd and Mr. 

 Eugene Smith participated. 



The second paper was by Mr. W. A. Can- 

 non, entitled 'Observations on the Structure 



of the Ovular Integuments of Dichelostemma 

 capitatum.' Colored figures were shown, in- 

 dicating the final absorption of the inner 

 integument by the developing endosperm. 

 The haustoria of the mistletoe penetrate the 

 oak cortex by secreting a ferment which dis- 

 solves the neighboring cell walls; excepting 

 certain lignified cells which become incor- 

 porated in the haustoria. So also in this 

 liliaceous plant, better known to many as 

 Brodiwa, the haustorial enzyme is unable to 

 dissolve the cuticularized membrane of the 

 integument. Possibly such cases of absorp- 

 tion of non-dissolved cuticularized membrane 

 may be widespread. 



Professor Lloyd in discussion suggested 

 that different parts of the ovule may be able 

 to secrete different kinds of enzymes, ready 

 to attack different kinds of tissues simulta- 

 neously; at least three different enzymes have 

 been obtained by mechanical means from the 

 yeast-plant. In certain of the Rubiaceas the 

 formation of enzymes in the megaspore ante- 

 dates fertilization; and that the pollen-tube 

 develops an enzyme is well known. 



The final contribution of the evening was 

 by Dr. N. L. Britton on the 'Morphology of 

 the fiower of Dichondra,' a plant commonly 

 assigned to the Convolvulacete. Its little 

 rotate flowers resemble a saxifrage and are 

 highly incongruous with the Convolvulaces. 

 Edward S. Buegess, 



Secretary. 



NORTHEASTERN SECTION OF THE AMERICAN 

 CHEMICAL SOCIETY. 



The regular monthly meeting of the Section 

 was held on Wednesday, March 26. .Professor 

 H. W. Conn, of Wesleyan University, pre- 

 sented an interesting paper on 'Some Aspects 

 of Commercial Bacteriology.' The early his- 

 tory of the use of butter cultures in Denmark 

 was reviewed, and the successful use of the 

 cultures in that country was attributed to the 

 law passed by the government requiring all 

 cream used in making butter to be Pasteur- 

 ized. This produces a mild butter with the 

 flavor characteristic of th'6 pure culture used. 

 In this country such a mild butter has not met 

 with ready sale, and if the cream has been 



