114 THE JOURNAL OF BOTANY 



Mr. Webber gives an historical account of the observations 

 made on hybridization in Maize by various writers, beginning with 

 P. Dudley's "An Observation on Indian Corn" (1724). This 

 writer remarks that "Indian corn is of several colours, as blue, 

 white, red, and yellow ; if these sorts are planted by themselves, 

 they will keep to their own colour. But if in the same field you 

 plant blue corn in one row of hills, and the white or yellow in the 

 next row, they will mix and interchange their colours ; that is, 

 some of the ears of corn in the blue-corn rows shall be white or 

 yellow ; and some in the white or yellow rows shall be of the blue 

 colour." Succeeding investigators made experiments on Maize 

 with the same result, that the influence of cross-fertilization could 

 be seen in the endosperm of the seed, either as a change of colour 

 or a change of form. It was also noted that the colour or form of 

 the hybrid endosperm was affected only where the cross occurred 

 with a plant of which the endosperm had had the same peculiarity. 

 If the pericarp of the seed of the crossing plant alone was coloured, 

 no trace appeared in the seed resulting from the cross-fertilization. 



Another conclusion Mr. Webber draws from his experiments is, 

 that though in every case change of endosperm or Xenia invariably 

 proved that the seed was a hybrid, and that such change was a 

 convenient check in plant-breeding experiments, yet the converse 

 did not hold true ; many seeds that showed no trace of Xenia 

 proved to be hybrids. He concludes that in these cases double 

 fertilization may not have taken place, and that the endosperm 

 could thus bear only the characters of the female plant. Mr. 

 Webber gives many examples in his excellent plates of the change in 

 colour and form produced in corn by Xenia ; he is to be congratulated 

 on the way in which he has shown how recent discoveries tally 

 with previous observations, so that what was once mysterious and 

 incomprehensible becomes a simple statement of cause and effect. 



A. L. S. 



Handbook of Practical Botany. By Dr. E. Strasburger. Trans- 

 lated and edited from the German, with many additional 

 notes, by W. Hillhouse, M.A., &c. Fifth edition, rewritten 

 and enlarged. Pp. xxxii, 519, with 150 original and a few 

 additional illustrations. London : Sonnenschein. 1900. 

 Price 10s. 6d. 



Dr. Strasburger's handbooks of practical botany are sufficiently 

 well known, both in the German and English form. For the latter 

 the English reading student owes a debt of gratitude both to the 

 translator and editor, and to the publisher. Messrs. Sonnenschein, 

 in the series of excellent and comparatively cheap botanical text- 

 books, have done good service — the familiar chocolate-brown -covered 

 volumes fill the chief place in the botanical library of the average 

 advanced student who does not aspire to the more ambitious and 

 more expensive green-backed translations issued by the Clarendon 

 Press. 



