ished, tawny to chestnut brown in color, and varying from 17 to 

 22 mm. in length. (See PI. IV, fig. 3.) From P. guanicana or 

 P. citri it is at once separable by its larger size, lighter color and 

 smoother surface. From P. portoricensis it is distinct in being con- 

 fined to a different habitat, as well as by the characters cited in 

 the preceding table. 



Unlike most species of PhyllopJiaga, vandinci may be found in 

 some abundance in the fields throughout at least eight and often 

 nine months of the year. In the Guanica district, where it has been 

 closely studied, it makes its first appearance during the last days 

 of February, and by the last of March is abundant, remaining so 

 from then up until late in September or tlie middle of October, wlien 

 it rapidly decreases in numbers ; and by the second week of Novem- 

 ber few are to be found in the fields. During the two years of 1914 

 and 1915, figures compiled by Guanica Centrale show that the beetles 

 were most abundant in 1914 from the last of July to early in Sep- 

 temlier. while in 1915 they were most plentiful from the middle of 

 April to early in July. These variations may be due to climatic con- 

 ditions in indi\adual seasons. 



As the life-cycle of the species covers only one year, or a period 

 of ten months for the actual egg-to-adult cycle, and as there is a 

 possible variation (as shown by breeding experiments) in this cycle 

 ranging from seven to tliirteen months, it is evident that there mugt 

 occur an overlapping of broods, to such an extent, in fact, as to dis- 

 tribute the emergence of adults over all of the sunnuer months. 



THE LIFE-HISTORY WORK. 



As this species is the worst cane pest of the Island, and the ulti- 

 mate object of all the experimental work on white-grubs Avas to find 

 a practical method of conti-oUing it, the laboratory-insectary erected 

 for its study, and called the South Coast Laboratory, was located at 

 Santa Rita, midway between Guanica and Yauco, in the heart of 

 the district worst infested by this beetle. ]\[ost of the white-gru)) 

 work was put upon the one species, with the result that its habits 

 and life-history are better known than those of ;iny otlier species 

 occurring on the Island. 



3Iore than twenty individuals of I'liilloplKif/d vanditwi wei'e 

 reared from egg to advilt. and twice as many more were reared suc- 

 cessfully to tlie pupal stage. Many hundreds of eggs from confined 

 adults were kept undei- observation, and the grubs hatching from 

 them were fed and regularly observed; l)ut a majority of tbese died 



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