674 General Notes. [August, 



only upon particular surface cells, and not indifferently upon any 

 of them. Only those surface cells which contain non-granular 



contents give rise to root hairs. In the Daily Spy of Worcester, 



Mass., Joseph Jackson, of the Worcester Natural History Society, 

 is publishing from time to time, lists of the plants of the season 

 as they appear, with pleasant notes upon many of them. It 

 would be a good thing for American botany if plant collectors 



generally were to follow Mr. Jackson's example. The Orange 



Judd Co., of New York, has brought out an American edition of 

 "The Chemistry of the Farm," by R. Warington, F. C. S. The 

 first five chapters are devoted to Plant Growth, Sources of Plant 

 Food, Manures, Crops, and Rotation of Crops, all more or less 

 botanical. In these chapters the matter is unusually good, the 

 latest views generally being adopted. The book can be heartily 



commended. A curious paper on "Pollen Tubes," appears in 



the June Am. Mo, Mic. journal, by J. Kruttschnitt. The writer 

 proposes the theory that "the pollen tubes insinuate themselves 

 amongst the papillae of the stigma where, on bursting, the fovilla 

 is taken up by the conducting tissue of the style." This con- 

 ducting tissue is supposed to convey the fovilla to the ovules ! 

 The editor of the Journal ought to have cut out the theory from 

 the article before publishing it, as it may mislead some of the 

 younger readers who are not well grounded in vegetable histology 



and physiology. Mention should have been made in these 



notes long ere this, of the slides prepared by Rev. A. B. Henry, 

 of Taunton, Mass., to illustrate the sexual and asexual repro- 

 duction of the Marine Algae. In set 1 six slides represent the 

 sexually produced spores of six different species, each representing 

 a family of the Floridiae according to Agardh's classification. 

 Set ii is made up of similar preparations, taking however a wider 

 range, and including species of lower orders. The sets may be 

 obtained for three dollars each, which, considering their great use- 

 fulness, is very cheap indeed. Professor Underwood is at work on 

 the Hepaticae of North America, and we may hope to receive from 



his hands, some day, a manual of these neglected plants. 



Professor Penhallow, of the Houghton Farm Experiment Station, 

 at Mountainville, Orange county, N. Y., has issued a circular 

 directing attention to many points in the life-history of the dis- 

 ease known as "peach yellows." We trust that as many of the 

 Naturalist readers as can do so, will aid in this work by corre- 

 spondence with the professor. The April Torrey Bulletin ap- 

 peared with nine full page plates, of which eight were illustrative 

 of Dr. Allen's paper on the " Development of Cortex in Chara. 

 The excellent work done by Dr. Allen on the Char« is one that 

 will commend itself to all students of plants. In the May bo- 

 tanical Gazette C. H. Peck describes fourteen new species of 

 fungi from California and Arizona. One, a remarkable species ot 

 Lycoperdon, is named L. pachydermum. 



