wliieh were still alive in the cells but had not eonie to the surface of ground wlien 

 the soil was dumped, July 30. Time, over 29 days. 



(2) No 548. — One female and two male adults, hatched in a battery jar on 

 July 3, 7 and 18, respectively, had not reached surface by July 30, though two 

 of them were still living. Time, over 3 2 to 27 days. 



(3) A o. 117zv. — A female, issued April 12 in a jar, had not come to rhe 

 surface on April 28, though still living. Time, over 16 days. 



(4) No. 1219h. — A female hatched Februai-y 15 and had not come to surface 

 through four inches of damp soil by March 10, though stdl alive. Time of pre- 

 emergence, over 23 days. 



DISTRIBUTION OF THE SPECIES. 



PhijUophaga vandinei is confined to the western end of the Island, 

 a territory equivalent to about one-third of the area of the Island. 

 Its eastern distribution may be defined, roughly, so far as our present 

 knowledge goes, by a north and south line across the Island through 

 the towns of ^lanati on the north and Peiiuelas on the south. Tlie 

 type of the species is from Santa Rita, near Guanica. 



The analogue of this species at the eastern end of the Island is 

 Phyllophaga portoricensis, which is indistinguishable from the former 

 species except by means of the genital characters given in the table. 

 It is indeed possible that the two are but races of one species, for 

 there seems to be a general intergrading of the characters along the 

 geographic line separating the two species. Yet at no time have the 

 two been taken in one locality ; and the specific characters are suffi- 

 ciently recognizable in specimens from the type localitit^s, Guanica 

 and Rio Piedras, to set apart the species as quite distinct. 



FEEDING HABITS OF THE ADFLT^. 



All May-beetles feed upon the foliage of plants and trees, and 

 are voracious eaters. The adult of vaiuUnci difi^ers from many species 

 of the genus in being a very general feeder, and there are few plants 

 which it will not touch. Feeding is done entirely at night, the adults 

 issuing from the ground at dark, or a little before. After a very 

 brief flight, they alight upon suitable foliage and begin to feed upon 

 the margins of the leaves. Feeding continues until very late into the 

 night, the beetles appearing to be as abundant after midnight as 

 before. Spending tlms six hours or more of the night in feeding, 

 they consume quantities of vegetation. Small tress of "quenepa, " 

 of "salcilla," and of native china-berry have been found completely 

 stripped of foliage by this species. Cane also sutt'ers from depre- 

 dations of the adults, but not to such an extent as the foliage of 

 certain trees. A common ornamental tree of the south side of the 



78 



