Tol. II, Mo. 9.] IKSECT LIFE. [March, 1890. 



SPECIAL NOTES. 



Professor Atkinson's Bulletin on Nematode Root-galls. —We have recently 

 received Bulletin No. 9, new series (Science Contributions, Vol. I, No. 1)> 

 of the Alabama Agricultural Experiment Station. It consists of U A 

 preliminary Eeport on the Life-history and Metamorphoses of a Koot-gall 

 Nematode, Heterodera radicicola (Graef) Mull., and the injuries produced 

 by it on the roots of various plants." It will be seen that the article 

 deals with the subject of Bulletin No. 20 of this Division, prepared by 

 Dr. Neal. Owing to the fact, stated in the preface to Bulletin No. 20 f 

 that Dr. Neal had not access to the literature of the subject, the inves- 

 tigation conducted by him aimed at the discovery of practical remedies 

 rather than scientific accuracy. 



The article of Professor Atkinson supplements Dr. Neal's work by 

 giving a careful and accurate account of the life-history and habits of 

 these worms; and as the author is evidently thoroughly familiar with 

 the European writings on Nematodes, little is left to be desired in this 

 direction. 



The species is referred with little doubt to Heterodera radicicola Mull., 

 which occurs commonly in central Europe in connection with a scarcely 

 distinct species R. schaclitii Schm. The genus Heterodera is shown to 

 be world-wide in distribution. In addition to the species mentioned, 

 one is found in Java in roots of sugar-cane: * in Brazil in roots of the 

 coffee-tree, and one is also recorded from Scotland — all of which are 

 scarcely distinguishable from H. radicicola. The structure and histo- 

 logical characteristics of diseased roots of various plants are discussed. 

 The disease of potatoes known as the " potato-scab," the early stages 

 of which are very like the Nematode galls on the potato tubers, the 

 " club-foot " of cabbage, and the functional tubercles on the roots of 

 Leguminosese, which have been shown to be of use to the plants in the 

 acquisition of nitrogen, are carefully distinguished from the quite sim- 

 ilar root-galls on these plants resulting from Nematode attack. 



* See note on page 85 of the present volume. 



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