773 



The Connecticut srECiES ofgymnosporanoiitm(cedaii apples), 

 R. TiiAXTEii, Pii. 1). (pp. 101-165).— A reprint of Bulletin No. 107 of 

 till' station (sec P^xperinieut Station Jlccord, vol. ii, j). 711). 



Fungus in vioeet roots, It. Thaxtek, Tii. J), (pp. 1G(;, 107).— 

 It^xaniinatioiis of the roots of diseased violet plants revealed the pres- 

 ence of great numbers of dark spots "commonly involving tlie whole 

 substance of the root for a distance of a few millimeters." 



St'ctious of .such spots show the tissue more or less blackened and destroj'ed, and 

 lying in the cells in j-reater or less numbers, certain peculiar lookinjr, scjnarisb l)rown 

 bodies, sometimes tilliug the cells completely and looking not unlike some form of 

 smut. These squarish 1)odie8 are the result of the breaking nj* of large cylindrical 

 2-5 (or more) septate brown spores formed from a rather scanty sejjtate mycelium 

 which apparently causes the death of the root cells at the affected points. 



The fungus is nndonbtedly the form described by Zopf (Sitz. d. Jiot. Ver.d. Prov. 

 llrandenb., June, 1S76, p. i(35) under the name Thielavia basicula, figun^d in Winter's 

 nize, vol. II, p. 4^, and also described and figured by Sorokin as i/c//«(/(//((>.sy>or««m 

 fruijUe {CUisUrospunnm frai/ile, Hacc.) in Bedivigiu, 1876, p. 113, where the (-harac- 

 teristic breaking up of the spores into squarish segments is well represented. 

 According to Zopf, the fungus is the same as the form described by Berkeley and 

 Broome {Ann. and Mag. of Nat. History, ser. ii, vol.v. No. 465, plate 11, fig. 4) as Torula 

 basicola, yet for reasons not mentioned all these are kept distinct by Saccardo. 



Zopf describes an ascosjjoric condition on which the genus Thielavia is fouiulcd, 

 which has not been observed by the writer except as a parasite on other fungi (spe- 

 cies of Isarla), and states that a very serious disease of the roots of Senecio is due 

 to its action. 



As regards the disease of violets, however', it seems doubtful whether the 

 observed injury done by the Thielavia would alone account for the condition of the 

 plants, yet the mere presence of a form supposed to cause serious disease in the roots 

 of other plants seems of sufficient interest to warrant the present note. 



Preliminary report on the so-called "pole burn" op 

 TOBACCO, W. 0. Sturgis, Ph. D, (pp. 168-184). — An account of the 

 origin of this disease and a discussion of methods for its prevention. 

 " Pole burn " is prevalent in Connecticut and other tobacco- growing 

 States, the severity of the disease varying in different years. 



As the disease was first brought to the notice of the writer it was seen to be char- 

 acterized by the apijearance on the surface of the leaf of small blackened areas, 

 giving the leaf the aspect of having been sprinkled with sulphuric acid or some 

 other corrosive liqnid. At first the disease is limited to the neighborhood of the 

 veins and midrib of the leaf, where moisture is superabundant, but its spread is 

 very rapid, the snuiU blackened areas increase in size, become confluent, and some- 

 times within 36 or at most 48 hours not only is the whole leaf affected, but the 

 entire contents of the curing barn may be rendered (juite worthless as tobacco. 

 Examinatioushowsthattheleaveshave changed frt)mgi('enish yellow to adark brown 

 or almost black color, that the fine texture has disai)peared, and that instead of 

 being tough and elastic the whole leaf is Avet and soggy, and tears almost with a 

 touch, falling f)f ifs own weiglit from the stalk. 



[Specimens of diseased leaves sent to the station in the fall of 1891 were sub- 

 jected to a thcn'ovigh micioscopic examination.] 



On the less damaged leaves the appearance w'as as described above, but a small 

 hand lens revealed in the center of each blackened spot a minute elevated pustule. 

 Sections through the center of one of these pustules showed that the tissue of the 

 leaf was largely disintegrated, and the cells themselves were completely filled with 



