NOTES AND ABSTRACTS. 



8ll 



Wounds, Treatment of, and Cavities in Trees (U.S.A. St. Com. 

 Hort., Cal., Bull. I ; 7, June 1912) describes the method of renovating 

 large holes in trees by filling in with Portland cement after removing 

 all dead and decaying wood. This usually preserves the tree for 

 many years. — V. G. J. 



Xenia. By E. M. East (Bot. Gaz., Sept. 1913, pp. 217-224).— The 

 author discusses the evidence derived from crossing experiments on 

 Mendelian lines so far as regards the morphological nature of 

 endosperm. The endosperm characters of maize are transmitted in 

 a perfectly regular manner and would tend (considered apart from 

 other facts) to show that the endosperm is sporophytic. 



But they accord perfectly with Coulter's view that the formation 

 of endosperm is an indefinite process resulting in a growth which is 

 practically gametophytic. — G. F. S. E. 



Yucca, Seed Production of. By Max M. Ellis (Bot. Gaz., July 

 1913, pp. 72-78). Yucca glauca grows both at Boulder and Wray, 

 Colorado. The flowers are pollinated by a single species of moth 

 which apparently is very local. Large numbers of Yuccas flower 

 every year and leave no seed because presumably the moth does 

 not visit them. 



The insect lays its egg in the ovary. As the larva grows, it 

 eats its way up through the centre of the column of flat seeds 

 which are stacked vertically in the pod like a pile of coins. The 

 lower seeds show a hole only one millimetre or so in diameter, 

 while the upper seeds are almost completely eaten, showing that the 

 larva greatly increases in diameter as it develops. 



On an average 280 seeds are found in a pod (maximum, 448 ; 

 minimum, 168). Of these, on an average 58, or 7 per cent., are 

 eaten by the larvae (o to 32 per cent.). There are 118 perfect seeds 

 as a rule in a pod and the plant on the whole is successful. 



The author discusses the advantage to the plant of the existence 

 of various parasitic insects which lay their eggs either in the egg 

 of the moth or in the larva. These parasites saved all the seeds 

 in seven pods, which considerably alters the averages.— G. F. S. E. 



Zoology, Manual of Practice in Economic. By H. A. Gossard 



(U.S.A. Exp. Stn. Ohio, Bull. 233; Nov. 1911 ; n plates) .—This 

 bulletin contains accounts and descriptions of most of the insects 

 that attack farm, garden, and orchard crops respectively. At the 

 end of the book are tables showing the remedies for prevention and 

 cure and the proper times of application. — V. G. J. 



Zygopetalum maxillare. By A. Braecklein (Orchis, vol. vii. 

 pt. v. pp. 75-76). — Zygopetalum maxillare will grow quite as well in 

 a mixture of Sphagnum and charcoal in pots or wooden boxes as it 

 does on fern stems. — S. E. W. 



