534 EXPERIMENT STATION EECOED. 



In the second part of the paper the author considers the secretion of water 

 in flowers,' and arrives at the conclusion that liquids are secreted not only by 

 the leaves but also in various parts of the flower. In his former conclusions 

 he considered the secretion of water in the flower bud as a useful arrange- 

 ment to protect the enclosed parts of the flower against desiccation, but as a 

 result of the later investigations he claims that the secretion by the glands of 

 the calyx and corolla is less exposed to evaporation in the closed calyx and 

 consequently collects there. In other words, the secretion of the water in the 

 flower bud did not originally arise because it was useful to the plant, but it 

 may be of advantage where the enclosed parts of the flower or fruit are exposed 

 to the danger of desiccation. 



The significance of mucilage in the germination of seed, C. Ravenna and 

 M. Zamoeani {Atti. R. Accad. Lineei, Rend. CI. Sci. Fis., Mat. e Nat., 5. ser., 19 

 {1910), II, No. 5, pp. 2Jf7-252). — Attention is called to the presence of mucilage 

 in the seeds of a number of species of plants, and an account is given of ex- 

 periments carried on by the authors with flaxseed to determine the function 

 of the mucilage. 



When the mucilage was removed from germinating seed, the seedlings pro- 

 duced showed less fresh and dry weight and a lower ash content than normally. 

 If, however, the mineral substances and carbohydrates represented by the muci- 

 lage were artificially supplied to the seed, the development proceeded as in 

 normal germination. 



It is claimed that the mucilage serves as a reserve material and that it is 

 utilized during germination. 



On the formation of hydrocyanic acid in germinating seed, C. Ravenna 

 and M. Zamorani {Atti. R. Accad. Lineei, Rend. CI. Sci. Fis., Mat. e Nat., 5. ser., 

 19 {1910), II, No. 7, pp. 356-361). — ^A summary is given of recent investigations 

 on the presence of hydrocyanic acid in germinating seeds, notably in the seeds 

 of Phaseolus lunatvs. Sorghum vulgare, and Linuvi usitatissimum. 



Experiments with etiolated plants and with seedlings grown in an atmosphere 

 free from carbon dioxid showed the presence of less hydrocyanic acid than 

 when the seedlings were grown under normal conditions. This indicates, it is 

 claimed, that carbohydrates play an important part in the formation of hydro- 

 cyanic acid. 



On the occurrence of the wild form of sugar beet, E. von Peoskowetz 

 {Ztschr. Ver. Deut. Zuckerindus., 1910, No. 657, II, pp. 987-1003, pis. ^.).— An 

 account is given of a wild form of beet found growing along the rocky coasts 

 of the Gulf of Quarnero of the Adriatic Sea. This plant, the author claims, is 

 the original species from which the cultivated beet was derived. 



The behavior of pure line cultures of Glomerella, C. L. Shear (Science, 

 n. ser., 32 {1910), No. 831, p. 808). — In a paper read before the sixty -fourth 

 regular meeting of the Botanical Society of Washington, the author reports the 

 study of pure line pedigreed cultures of a species of Glomerella obtained from 

 an aeervulus on a leaf of the avocado {Persea gratissiyna). Twenty-three suc- 

 cessive generations were grown from this culture and carefully compared with 

 each other. Single ascospore cultures obtained in the same manner from the 

 same initial cultures were studied through 7 generations. 



Variations in all the characters of the organisms occurred, especially in the 

 conidial and perithecial fructifications. Some of the characters after being 

 transmitted for several generations either suddenly or gradually disappeared, 

 to reappear in later generations. 



As the physical, chemical, and biological environments of the organism were 

 supposed to be the same, it seems probable that some of these sudden and strik- 

 ing variations should be referred to other factors than those of environment. 



