Bonnier suggests that the electric light may be used to determine which 

 of these are most constant.— Erwin F. Smith. 



A Graft Hybrid.— At a meeting of the Biological Society in 

 Christiana, Nov. 21, 1895, Prof. N. Wille, the well known algologist, 

 exhibited the fruit and leaves of a so-called graft hybrid which is said 

 to have resulted from the working of a pear upon a white thorn {Cra- 

 taegus oxyacantha L.). This tree stands in the Hofe Torp in Borge 

 EQrchspiel in southeast Norway. According to the statement of Herr 

 Apotheker Johns. Smith, of Fredriksstad, the tree is about twenty years 

 old and stood for fifteen years in an unfavorable place without blos- 

 soming. It wa then set in a better place and has blossomed and borne 

 fruit for five years. The flowers are like those of the pear tree but 

 somewhat smaller and borne in corymbs like those of Crataegus. The 

 pedicels and the fruit are smooth, but the calyx lobes are triangular 

 and woolly hairy with the tips somewhat bent back. The small fruits 

 (1-5 to 3 cm. long by 1-3 to 2 cm. broad) are pear-shaped but with the 

 color of Crataegus fruits. The fruits are five-celled and usually with 

 two sterile seeds in each compartment ; the pericarp is somewhat firmer 

 than the flesh of the fruit and recalls the so-called stone of the Cratae- 

 gus fruit, but is by no means so hard. The taste of the flesh is insipid 

 and lies between the taste of the pear and that of the white thorn. 

 All the fruits examined by Prof. Wille contained only sterile seeds, 

 but Herr Apotheker Smith stated to him that he once found a single 

 perfect seed. The leaves of the tree have retained the appearance of 

 pear leaves and do not appear to be changed, but out of the wild stem 

 below the point of union shoots of the white thorn now and then grow 

 out and these have the characteristic leaves of that tree. This account 

 is taken from Biologisches Centralblatt, Bd. 16, No. 3, Feb. 1, 1896. It 

 would add much to the credibility of this case if it could be learned 

 when, by whom, and from what sort of pear tree this white thorn was 

 grafted. A sceptical pomologist suggests that the top of this tree may 

 possibly be the Japanese Pirus Toringo, or some allied species. — Erwin 



Ustilaginoidea. The following note should have appeared in the 

 March number of this journal, p. 226, after Biology of Smut Fungi, 

 in connection with which it should be read. 



Note.— Since the above was written, Dr. Brefeld has succeeded in 

 discovering the full life history of Ustilaginoidea. The sclerotia, after 

 lying on damp sand for six months, developed an ascus fructification 

 closely resembling Claviceps. Dr. Brefeld's last paper on the subject 



