232 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 6 



The cane in this field was young plant cane, that is, cane at the begin- 

 ning of its first year of growth. 



The larvae and pupse collected at Mameyes on November 23, 1912, 

 were taken from a field containing, it is estimated, twenty-six acres. 

 The leaves of the cane plants over an area of some four acres had been 

 eaten to the midribs by the larvae of Laphygma frugiperda and Remi- 

 gia repanda. The degree of injury to the cane over the remainder of 

 the field, as well as in adjoining fields, varied. Unfortunately, at the 

 time of the writer's visit to this locality, the greater proportion of 

 the destructive brood of "grass worms" had completed their develop- 

 ment and pupated. Comparative notes on the abundance of the two 

 species could, therefore, not be made. The leaves of old ratoon cane 

 in a nearby field, the plants being some six or seven feet in height, had 

 also been attacked by "grass worms." The amount of defoliation 

 here did not appear to be as great as on the young cane, though it 

 must be borne in mind that the same amount of defoliation would 

 be more evident on the young cane. 



There was a considerable growth of "malojillo" in parts of the fields 

 and in some sections this had been "stripped." It appeared, however, 

 that the degree of injury to the cane in various parts of the attacked 

 areas did not depend upon the presence or absence of grass in those 

 parts. 



On January 11, 1912, larvae of Laphygma frugiperda and Remigia 

 repanda, the greater proportion full grown, occurred in enormous 

 numbers at Rio Piedras over an area that had been overflowed during 

 the previous month. Part of the section on which they were present 

 was in pasture; the grass growing on the land being largely "malo- 

 jillo." Part of a field of "malojillo," the crop on which was about 

 three feet high, and part of a field of young sugar cane was also being 

 attacked. The larvae had "stripped" the grass and cane so that only 

 the grass stems and the stalks and midribs of the cane remained. 

 When seen from a distance, the area was well defined, the difference 

 in color between it and the uninjured vegetation bordering it being 

 well marked. 



Injury in the La Plata river valley, following floods that occurred 

 at the same time as did those at Rio Piedras, was reported to Mr. Van 

 Dine by Mr. P. H. Gorman of the Porto Rican-American Tobacco 

 Company. The writer visited the valley on January 23, 1912, but 

 found very few "grass worms," though the results of their feeding 

 on the grass in the valley was just as pronounced as at Rio Piedras, 

 part of the area where they had been so plentiful being some distance 

 above the area previously overflowed. The writer was told that the 

 "worms" had, at one point in the valley, damaged tobacco plants to 



