230 AGRICULTUKAL EXPERIMENT STATION. [Jan. 



6. The Leaf Glaze. — Acremonium sj). (Plate IV.) 



Early in ISDl cucuml^er leaves Avere received from Fitch- 

 burg, INIass., whose lower surfaces showed delicate glairy 

 films of fungus-threads, as described in our last report.* 

 These leaves came from very badly diseased plants, which 

 had received no benefit from the application of fungicides, 

 although it seemed probable that the accompanying fungus 

 bore some causal relation to the trouble. The fungus-threads 

 on the leaves were quite sterile when received, but, when the 

 leaf bearing them had lain two or three days in the moist 

 chamber, produced spores abundantly. Drawings showing 

 the structure of the fungus and the germination of its spores 

 were made at the time and laid aside, in the hope that addi- 

 tional material would make possible an extension of our 

 knowledge of the disease and of the relations of the fungus 

 in question to it. As it has not again been met with, no 

 further information can be given concerning it, and we can 

 only complete the record of our meagre knowledge of the 

 subject by publishing herewith the drawings mentioned. 



The film on the leaves consists of numerous delicate, 

 colorless and closely interwoven threads. These give rise 

 in the moist chamber, and probably sooner or later under 

 natural conditions, to short simple threads at right angles 

 (fig. 27), at the slightly knobl^ed apex of each of which is 

 produced a single somewhat kidney-shaped spore (fig. 28). 

 In water these spores swell up and produce stout germ tubes 

 of considerable leno;th, similar to the original threads of the 

 film (fig. 29). This is all we know of the fungus. It is to 

 be hoped that some investigator may be a1)le to study it in 

 detail, with the disease it accompanies, and to answer the 

 many interesting questions concerning it which still await an 

 answer. 



7. Othek Diseases. 



Two other diseases of some importance, which have ngt 

 yot been observed in Massachusetts, but may at an}^ time l)e 

 met with, may be briefly mentioned in conclusion. 



Halsted has descril)ed f a serious rotting of cucumbers and 



* Ninth Report Massachusetts Experiment Station, p. 227. 



t Botanical Gazette, 1891, p. 303; and Twelfth Report New Jersey Station, p. 273. 



