342 



Gloyer (W. 0.) & Fulton (B. B.). Tree Crickets as Carriers of 

 Leptosphaeria coniothyrium, (Fckl.) Sacc, and other Fungi. — New 

 York Agric. Expt. Sta., Geneva, Tech. Bull. no. 50, March 1916, 

 22 pp., 2 tables, 4 plates. [Received 6th June 1916.] 



This paper describes further experiments carried out with the object 

 of determining the part played by Oecanthus spp. in spreading canker 

 among fruit trees. Previous records assert that these insects carry 

 the spores of Leptosphaeria coniothyrium, and suggest that spores of 

 other fungi may also be distributed in this way. Cankers caused by 

 L. coniothyrium are similar in their early stages to those due to Bacillus 

 amylovorus, S^yhaeropsis 7nalorum or Glomerella cingulata, but are 

 readily distinguishable at a later period. L. coniothyrium cankers are 

 always associated with the oviposition punctures of tree-crickets, and 

 show rapid increase in size just before the flowering period. Periods 

 of activity on the part of the fungus alternate with periods of quiescence. 

 The host endeavours to protect itself by the formation of a callus 

 between the healthy and diseased tissue. The callus may exhibit 

 irregularities and is apparently stimulated to further growth by the 

 presence of woolly aphis [Eriosoma lanigerum], which shelter there. 

 Fungus spores are present in large numbers beneath and on the surface 

 of the bark of cankers which are two or more years old. Sphaeropsis 

 malorum, Valsa leucostoma and certain saprophytes may also be 

 present. Young trees of JJlmus americana, growing among tall weeds, 

 may show superficial cankers due to L. coniothyrium and with this 

 fungus may be associated Pestalozzia insidiens. 



Spores of L. coniothyrium may be introduced into oviposition 

 punctures in the following ways : — (1) with excrement or vegetable 

 tissue used in plugging the punctures ; (2) with the ovipositor ; 

 (3) by being washed in by rain. 



Experiments were made to determine the effect on the fungus spores 

 of passage through the alimentary canal of tree-crickets. Excrement 

 obtained from insects kept in captivity and from the vicinity of 

 oviposition punctures showed the spores of several kinds of fungi 

 (Sphaeropsis malorum, L. coniothyrium, Mucor, Pucoinia, etc.), 

 Bacteria, yeasts, and spores of the Protozoan, Gregarina. Many of 

 the spores germinated when placed under suitable conditions. In the 

 case of L. coniothyrium and Nummularia discreta, germination is much 

 more rapid in the presence of apple wood than in water, while both are 

 equally suitable for S. malorum. Apple cankers can be artificially 

 produced from spores obtained from the excrement of Oecanthus 

 angustipennis and 0. niveus. Under the experimental conditions, 

 these two species when fed with pure cultures of L. coniothyrium from 

 apple cankers produced a lower percentage of disease than when fed 

 with raspberry leaves infested with the same fungus. The percentage 

 of infection was always greater in cases in which the oviposition 

 punctures were closed with grafting wax. 



Haseman (L.). Ornix geminatella, the Unspotted Tentiform Leaf Miner 

 of Apple." — Jl. Agric. Research. Washington, D.C., vi, no. 8, 

 22nd May 1916, pp. 289-296, 1 plate. 



Parornix (Ornix) geminatella. Pack., has been recorded from New 

 England, Colorado, Kentucky, Michigan, Illinois and Ohio. The 



