been observed in isolated eanes, (generally insect injured stalks), 

 of a number of varieties. 



In the (7ase of one variety only, D-625, has it been noted acting 

 apparently alone. Other surrounding varieties in this instance re- 

 mained normal, but of the D-625 fully twenty-five per cent of the 

 stalks were attacked. The only external symtom was the withering 

 and dying of attacked stalks from the top downward, in no way dif- 

 ferent from the death of a stalk from any one of many other causes. 



Internally was found a very striking rot, which at once distin- 

 guished the disease from any other. The rotted areas extended from 

 the top downward, rapidly covering the entire length of the stalk, 

 and attacking the bundles first, which became red in color. The red 

 coloration soon became uniform throughout the central pith region, 

 bordered by an outer periphery of normal tissues. The attacked tis- 

 sues were somewhat rubbery in consistency, lacking in juice, and 

 rapidly turned brown on exposure to air. The rot finally worked 

 through to the surface producing irregular brown patches on the 

 internodes which finally coalesced. Canes after three months in the 

 laboratory have not yet produced fruiting bodies. Melanconiiim sac- 

 chari was occasionally present as a secondary organism. The color 

 of the rot was much deeper than that produced by CoUetotrichum, 

 the areas were more uniform, and the white patches characteristic 

 of red rot were lacking. Diplodia was obtained in cultures. 



This fungus, originally described from twigs of cacao, ha.s been 

 reported on cane l)y Butler (10) in British India and by Howard 

 (41) in Barbados. The former described it as usually saprophytic 

 only, but the latter found it at times parasitic and was able by inocu- 

 lations to reproduce the disease said to be caused by it. Averna-Sacca 

 (100) gives an account of a disease ascribed to Lasiodiplodia theo- 

 hromae, which is doubtless the same species. 



It is extremely doubtful if it will ever be of -any real economic 

 importance in Porto Rico, since it attacks only injured canes or Aveak 

 varieties. D-625 being notoriously of such a nature. 



3IELANC0NIUM SACCHARINUM ( ?) PcUZ. Ct SaCC. 



Acervuli hypophyllous, gregarious, longitudinally seriate, o])long, 

 1 mm. long, by ..i wide, lilack, hysterioid eruriipcnl: conidin large, 

 globose compressed. 24X14 mu. black, smooth, borne on filiform, 

 hyaline pedicels. Description after Saccardo. 



Porto Rico. — On cane leaves, Rio Piedras, Dec, 1911, 4111, 4112, 

 4142, 4143, 4144, 4145, 4146, March 1912, 4294, June, 1917, 6559; 

 Mercedita, Jan., 1912, 4171 ; Fajardo, March, 1912, 4291. On Cijm- 



221 



